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All questions of Scientific Processes for Grade 9 Exam
What is the physical state of water at 100°C?
- a)both gaseous and liquid state
- b)solid state
- c)liquid state
- d)gaseous state
Correct answer is option 'A'. Can you explain this answer?
What is the physical state of water at 100°C?
a)
both gaseous and liquid state
b)
solid state
c)
liquid state
d)
gaseous state
|
Arvind Singh answered |
At 100°C, water exists in both the liquid state as well as in gaseous state. This is special condition because 100°C is the boiling point of water and as well as liquefaction temperature of the water vapour
Can you explain the answer of this question below:Transpiration from the leaves of trees is an example of:- A:Evaporation
- B:Sublimation
- C:Condensation
- D:Diffusion
The answer is a.
Transpiration from the leaves of trees is an example of:
A:
Evaporation
B:
Sublimation
C:
Condensation
D:
Diffusion
|
|
Amit Sharma answered |
Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
What is the physical state of water at100C?- a)Liquid
- b)Solid
- c)gas
- d)All of these
Correct answer is 'B'. Can you explain this answer?
What is the physical state of water at100C?
a)
Liquid
b)
Solid
c)
gas
d)
All of these
|
|
Arjun Sharma answered |
The answer is a .
The physical state of water at its boiling point temperature of 100 degree Celsius will be both liquid state as well as gaseous state. This is because at its boiling point of 100 degree celsius the liquid state of water starts changing into its Gaseous state (steam).
The change of state from solid to liquid known as –
- a)Melting
- b)Boiling
- c)Sublimation
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
The change of state from solid to liquid known as –
a)
Melting
b)
Boiling
c)
Sublimation
d)
None of these
|
|
Amit Sharma answered |
The change of state from solid to liquid is known as Melting. This is a process in which a solid substance changes into a liquid on heating. Heat energy is required to break the bonds between molecules, allowing them to move around freely. This process is also known as fusion, and the amount of energy required is called the latent heat of fusion. In a phase diagram such as Figure 12.4.1, the melting point is the temperature at which a substance can transition from a solid to a liquid.
Rate of diffusion is the fastest in- a)Solids
- b)Liquids
- c)Gases
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Rate of diffusion is the fastest in
a)
Solids
b)
Liquids
c)
Gases
d)
None of these
|
|
Neeraj! answered |
Rate of diffusion is the fastest in Gases
Natural phenomenon like fog, mist or frost are caused due to:- a)Evaporation
- b)Transpiration
- c)Freezing
- d)Condensation
Correct answer is option 'D'. Can you explain this answer?
Natural phenomenon like fog, mist or frost are caused due to:
a)
Evaporation
b)
Transpiration
c)
Freezing
d)
Condensation
|
Jyoti Kapoor answered |
Fog, mist or frost are due to condensation, depending upon the physical conditions of atmosphere.
Which substance undergo sublimation process –
- a)Naphthalene
- b)Br2
- c)Ice
- d)N2
Correct answer is option 'A'. Can you explain this answer?
Which substance undergo sublimation process –
a)
Naphthalene
b)
Br
2c)
Ice
d)
N2
|
Ruhi Shah answered |
Some substances that undergo sublimation include dry ice (solid carbon dioxide), iodine, camphor, and napthalene.
Under which of the following conditions we can boil water at room temperature?
- a)At low pressure
- b)At moderate pressure
- c)At very high pressure
- d)At atmospheric pressure
Correct answer is option 'A'. Can you explain this answer?
Under which of the following conditions we can boil water at room temperature?
a)
At low pressure
b)
At moderate pressure
c)
At very high pressure
d)
At atmospheric pressure
|
Varun Kumar answered |
At low pressure
Explanation: Boiling occurs when the vapor pressure of a liquid equals the external pressure. At lower pressures, the boiling point of water decreases. So, if the external pressure is reduced significantly (below atmospheric pressure), water can boil at room temperature. This phenomenon can be observed in a vacuum chamber, where the pressure is significantly reduced, allowing water to boil at room temperature.
Explanation: Boiling occurs when the vapor pressure of a liquid equals the external pressure. At lower pressures, the boiling point of water decreases. So, if the external pressure is reduced significantly (below atmospheric pressure), water can boil at room temperature. This phenomenon can be observed in a vacuum chamber, where the pressure is significantly reduced, allowing water to boil at room temperature.
An Almirah is a solid because its- a)hard and rigid
- b)shape doesn’t change when pressed
- c)density is very high
- d)All of these
Correct answer is 'D'. Can you explain this answer?
An Almirah is a solid because its
a)
hard and rigid
b)
shape doesn’t change when pressed
c)
density is very high
d)
All of these
|
Jhanvi Mukherjee answered |
An almirah is solid because it is hard and rigid, have fixed shape and have very high density. All these properties are possessed by solid substance only.
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility.- a)True
- b)False
Correct answer is 'A'. Can you explain this answer?
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility.
a)
True
b)
False
|
Hansa Sharma answered |
The large volumes of gases can be put into small volumes of cylinders because of their property known as compressibility. This is possible because of the large inter particle distance and weak force of attraction between the particles of gas.
The boiling point of water on kelvin scale is –- a)573 K
- b)273 K
- c)373 K
- d)100 K
Correct answer is 'C'. Can you explain this answer?
The boiling point of water on kelvin scale is –
a)
573 K
b)
273 K
c)
373 K
d)
100 K
|
Om Menon answered |
Formula to change the value of celcious into kelvin is K=C+273 As we know that boiling point of water is 100 c. SO, K=100+273 K =373 k.
Gases have highest rate of diffusion among all the three states of matter.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Gases have highest rate of diffusion among all the three states of matter.
a)
True
b)
False
|
|
Amit Kumar answered |
Diffusion is the property of matter which is based on the motion of its particles. Diffusion occurs in gases, liquids and solids. Diffusion is fastest in gases and slowest in solids. The rate of diffusion increases on increasing the temperature of the diffusing substance.
Can you explain the answer of this question below:Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Matter in our surroundings" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 Science Q. Which of the following has the strongest interparticle force at the room temperature?- A:Nitrogen
- B:Mercury
- C:Iron
- D:Chalk
The answer is C.
Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Matter in our surroundings" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 Science
Q. Which of the following has the strongest interparticle force at the room temperature?
A:
Nitrogen
B:
Mercury
C:
Iron
D:
Chalk
|
Sharanya shah answered |
Higher the melting point of a substance, greater will be the force of attraction between particles. The melting point of iron is considerably high, so the force of attraction between its particles is higher.
Convert the temperature of 373°C to the kelvin scale ?- a)646 K
- b)546 K
- c)300 K
- d)500 K
Correct answer is option 'A'. Can you explain this answer?
Convert the temperature of 373°C to the kelvin scale ?
a)
646 K
b)
546 K
c)
300 K
d)
500 K
|
Nikhil Mehra answered |
We know that ,K = °C + 273.15
= 373 deg C + 273.15 deg C
= 646.15 deg C
Name one common substance which can undergo a change in state upon heating or cooling.- a)Salt
- b)Water
- c)Sugar
- d)All of these
Correct answer is option 'B'. Can you explain this answer?
Name one common substance which can undergo a change in state upon heating or cooling.
a)
Salt
b)
Water
c)
Sugar
d)
All of these
|
|
Hansa Sharma answered |
Water can undergo a change in state upon heating and cooling. On heating above 1000C water change into gaseous state and on cooling below 00C it changes into solid state.
Water has boiling point equal to 100°C.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Water has boiling point equal to 100°C.
a)
True
b)
False
|
Zzz answered |
It is true as boiling point of water is 100 degree Celsius, the statement is absolutely true and correct
Camphor changes to gaseous state without changing into liquid.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Camphor changes to gaseous state without changing into liquid.
a)
True
b)
False
|
|
Jithin Das answered |
It's true because camphor is sublime and it changes directly into gas without passing through the state of liquid. The process in which solid directly changes into gas without passing through the state of liquid is called sublimation.
Which of the following is not a compound?- a)marble
- b)washing soda
- c)quick lime
- d)brass
Correct answer is option 'D'. Can you explain this answer?
Which of the following is not a compound?
a)
marble
b)
washing soda
c)
quick lime
d)
brass
|
Yuvraj Singhaniya answered |
Compound is the combination of two or more elements chemically but brass is a mixture of two elements
The process of change of a liquid into vapour at any temperature is called –- a)Diffusion
- b)Evaporation
- c)Cooling
- d)Heating
Correct answer is option 'B'. Can you explain this answer?
The process of change of a liquid into vapour at any temperature is called –
a)
Diffusion
b)
Evaporation
c)
Cooling
d)
Heating
|
Ravi Verma answered |
The process of conversion of a substance from the liquid state to its vapor state at any temperature below boiling point is called evaporation or vaporization.
The evaporation of a liquid occur only at- a)temperature more than 1000C
- b)temperature less than 1000C
- c)fixed temperature
- d)all temperatures
Correct answer is option 'D'. Can you explain this answer?
The evaporation of a liquid occur only at
a)
temperature more than 1000C
b)
temperature less than 1000C
c)
fixed temperature
d)
all temperatures
|
|
Ananya Sharma answered |
Evaporation is the process of conversion of liquid into gas below its boiling point.
Evaporation can occur at any temperature. Where as Boiling occurs at a specific temperature called as Boiling point.
Examples which can prove that evaporation can occur at any temperature:
1. Evaporation of water from water bodies.
2. Evaporation of water from wet clothes.
3. Evaporation of acetone when exposed to open air.
Temperature is one of the factor which effects the rate of EVAPORATION.
If temperature is more rate of EVAPORATION will be more.
Can you explain the answer of this question below:Evaporation causes heating
- A:
True
- B:
False
The answer is B.
Evaporation causes heating
True
False
|
|
Arjun Sharma answered |
When evaporation occurs then than the liquid (mostly water) absorbs all the heat from the surroundings and take it with it and we feel cool. evaporation causes cooling effect because the heat energy is abosorbed by surrounding particles.
Can you explain the answer of this question below:Pressure on the surface of a gas is increased. What will happen to the inter-particle forces?
- A:
They will remain constant
- B:
They will increase
- C:
They will decreases
- D:
None of these
The answer is b.
Pressure on the surface of a gas is increased. What will happen to the inter-particle forces?
They will remain constant
They will increase
They will decreases
None of these
|
|
Anita Menon answered |
Increase in the pressure on the surface of a gas decreases the volume of the gas with increasing its density. The particles start moving in straight lines and also collide with the wall of the container and this collision enhances the inter particle forces and increases the fluidization behaviour.
Name the process by which a drop of ink spreads in a beaker of water –
- a)Diffusion
- b)Vaporization
- c)Condensation
- d)Sublimation
Correct answer is option 'A'. Can you explain this answer?
Name the process by which a drop of ink spreads in a beaker of water –
a)
Diffusion
b)
Vaporization
c)
Condensation
d)
Sublimation
|
Prachi Rathore answered |
A drop of ink spreads in a beaker of water through diffusion. This is because the particles in liquids can move around each other, which means that eventually they are evenly mixed. Diffusion is the process of a substance spreading out to evenly fill its container or environment. In a solution, a concentrated solute diffuses to spread evenly in its solvent. concentration to low concentration.
The temperature at which liquid starts boiling at atmospheric pressure known as –- a)Melting point
- b)Boiling point
- c)Latent heat
- d)Condensation
Correct answer is option 'B'. Can you explain this answer?
The temperature at which liquid starts boiling at atmospheric pressure known as –
a)
Melting point
b)
Boiling point
c)
Latent heat
d)
Condensation
|
Sarita Reddy answered |
Boiling occurs when the vapor pressure reaches or exceeds the surrounding pressure from the atmosphere or whatever else is in contact with the liquid. At standard atmospheric pressure (1 atmosphere = 0.101325 MPa), water boils at approximately 100 degrees Celsius.
Fluids are –- a)Liquids and gases
- b)Solids and gases
- c)Liquids and solids
- d)Only solids
Correct answer is option 'A'. Can you explain this answer?
Fluids are –
a)
Liquids and gases
b)
Solids and gases
c)
Liquids and solids
d)
Only solids
|
|
Arvind Singh answered |
In physics, a fluid is a substance that continually deforms under an applied shear stress. Fluids are a subset of the phases of matter and include liquids, gases, plasmas, and to some extent, plastic solids.
The melting points of two solids [A] and [B] are 300K and 350K respectively. Which has more inter-particles forces?- a)[A]
- b)both have same inter-particles forces
- c)Information not enough.
- d)[B]
Correct answer is option 'D'. Can you explain this answer?
The melting points of two solids [A] and [B] are 300K and 350K respectively. Which has more inter-particles forces?
a)
[A]
b)
both have same inter-particles forces
c)
Information not enough.
d)
[B]
|
|
Ananya Das answered |
With increase in temperature, inter-particles forces decreases. As the melting point of solid A is less than Solid B. Solid B has more inter-particle forces of attraction. Higher the melting point more the inter-particle force.
Which of the following solids undergo sublimation upon heating?- a)Ice
- b)Urea
- c)sugar
- d)Iodine
Correct answer is option 'D'. Can you explain this answer?
Which of the following solids undergo sublimation upon heating?
a)
Ice
b)
Urea
c)
sugar
d)
Iodine
|
|
Hansa Sharma answered |
The process of changing solid directly into gases without changing into liquid is called sublimation. In the substance given above only Iodine is a sublime substance.
Match the following with correct response.
(1) Dry ice
(2) Humidity
(3) Temperature
(4) Liquefied gas
(A) Reduce evaporation
(B) Increasing pressure reducing temperature
(C) Increases evaporation
(D) Solid carbon-dioxide- a)1-B, 2-D, 3-A, 4-C
- b)1-C, 2-B, 3-D, 4-A
- c)1-D, 2-A, 3-C, 4-B
- d)1-A, 2-C, 3-B, 4-D
Correct answer is option 'C'. Can you explain this answer?
Match the following with correct response.
(1) Dry ice
(2) Humidity
(3) Temperature
(4) Liquefied gas
(A) Reduce evaporation
(B) Increasing pressure reducing temperature
(C) Increases evaporation
(D) Solid carbon-dioxide
(1) Dry ice
(2) Humidity
(3) Temperature
(4) Liquefied gas
(A) Reduce evaporation
(B) Increasing pressure reducing temperature
(C) Increases evaporation
(D) Solid carbon-dioxide
a)
1-B, 2-D, 3-A, 4-C
b)
1-C, 2-B, 3-D, 4-A
c)
1-D, 2-A, 3-C, 4-B
d)
1-A, 2-C, 3-B, 4-D
|
|
Raghav Bansal answered |
solid carbon dioxide is known as dry ice. The reduced evaporation is called humidity. Evaporation is increased by temperature. The liquefied gas increases pressure and reduces temperature.
The process for the change of a solid directly into its vapour is called –- a)Evaporation
- b)Ebullition
- c)Condensation
- d)Sublimation
Correct answer is option 'D'. Can you explain this answer?
The process for the change of a solid directly into its vapour is called –
a)
Evaporation
b)
Ebullition
c)
Condensation
d)
Sublimation
|
Sanchita Choudhury answered |
Sublimation is the process through which the solid substance changes directly into vapours or gaseous state without passing through liquid state. Dry ice is a common example of this process.
Convert the temperature of 270 K to the celsius scale –- a)– 3°C
- b)– 4°C
- c)2°C
- d)5°C
Correct answer is option 'A'. Can you explain this answer?
Convert the temperature of 270 K to the celsius scale –
a)
– 3°C
b)
– 4°C
c)
2°C
d)
5°C
|
|
Amit Kumar answered |
We know that °C = K - 273.15
C= K - 273
C= 270 - 273
C = -3
C= 270 - 273
C = -3
Sulphur dioxide is collected in the lab in a gas jar by upward displacement of air. Which of the following statement is correct regarding the density of the gas?- a)No correct statement can be made about the density of the gas.
- b)It is lighter than air
- c)It is heavier than air
- d)Its density is equal to that of air
Correct answer is option 'C'. Can you explain this answer?
Sulphur dioxide is collected in the lab in a gas jar by upward displacement of air. Which of the following statement is correct regarding the density of the gas?
a)
No correct statement can be made about the density of the gas.
b)
It is lighter than air
c)
It is heavier than air
d)
Its density is equal to that of air
|
|
Amit Sharma answered |
At room temperature, sulfur dioxide is a nonflammable, colorless gas that is heavier than air. Its strong, pungent odor and irritating properties usually provide adequate warning of its presence.
A substance upon heating directly changes into gaseous state. What is this change called?- a)Melting
- b)Fusion
- c)Sublimation
- d)Condensation
Correct answer is option 'C'. Can you explain this answer?
A substance upon heating directly changes into gaseous state. What is this change called?
a)
Melting
b)
Fusion
c)
Sublimation
d)
Condensation
|
|
Neeti Gupta answered |
Sublimation
Sublimation is the process in which a substance directly changes from a solid to a gaseous state without passing through the liquid phase. This change occurs when the substance is heated to a temperature at which its vapor pressure exceeds the atmospheric pressure. Sublimation is an endothermic process, meaning that it requires energy in the form of heat to occur.
Examples of Sublimation:
1. Dry ice - When dry ice, which is solid carbon dioxide, is heated it directly changes into carbon dioxide gas without melting into a liquid.
2. Camphor - When camphor is heated, it directly changes into a gaseous state without melting.
3. Naphthalene balls - Naphthalene balls used for moth control also undergo sublimation on heating.
Uses of Sublimation:
1. Sublimation is used in the purification of substances. For example, when impure solid iodine is heated, it directly changes into iodine vapor, which can be collected and condensed into pure solid iodine.
2. Sublimation is used in the production of certain chemicals, such as in the production of semiconductor materials.
3. Sublimation is also used in the manufacturing of dry ice, which is used in refrigeration and transportation of food and medical products.
Conclusion:
Sublimation is a process in which a substance directly changes from a solid to a gaseous state without passing through the liquid phase. It is an important process with various industrial and scientific applications.
Sublimation is the process in which a substance directly changes from a solid to a gaseous state without passing through the liquid phase. This change occurs when the substance is heated to a temperature at which its vapor pressure exceeds the atmospheric pressure. Sublimation is an endothermic process, meaning that it requires energy in the form of heat to occur.
Examples of Sublimation:
1. Dry ice - When dry ice, which is solid carbon dioxide, is heated it directly changes into carbon dioxide gas without melting into a liquid.
2. Camphor - When camphor is heated, it directly changes into a gaseous state without melting.
3. Naphthalene balls - Naphthalene balls used for moth control also undergo sublimation on heating.
Uses of Sublimation:
1. Sublimation is used in the purification of substances. For example, when impure solid iodine is heated, it directly changes into iodine vapor, which can be collected and condensed into pure solid iodine.
2. Sublimation is used in the production of certain chemicals, such as in the production of semiconductor materials.
3. Sublimation is also used in the manufacturing of dry ice, which is used in refrigeration and transportation of food and medical products.
Conclusion:
Sublimation is a process in which a substance directly changes from a solid to a gaseous state without passing through the liquid phase. It is an important process with various industrial and scientific applications.
When the liquid starts boiling, the further heat energy which is supplied- a)is lost to the surrounding as such
- b)increases the K.E of the particle in the liquid
- c)Increases the temperature of the liquid.
- d)is absorbed as latent heat of vaporization by the liquid
Correct answer is option 'D'. Can you explain this answer?
When the liquid starts boiling, the further heat energy which is supplied
a)
is lost to the surrounding as such
b)
increases the K.E of the particle in the liquid
c)
Increases the temperature of the liquid.
d)
is absorbed as latent heat of vaporization by the liquid
|
Prerna Desai answered |
When the liquid starts boiling, the further heat energy which is supplied is absorbed as latent heat of vaporization by the liquid to change its state of matter.
Plasma is the.......... state of matter –- a)First
- b)Second
- c)Third
- d)Fourth
Correct answer is option 'D'. Can you explain this answer?
Plasma is the.......... state of matter –
a)
First
b)
Second
c)
Third
d)
Fourth
|
|
Ananya Sharma answered |
A plasma is a hot ionized gas consisting of approximately equal numbers of positively charged ions and negatively charged electrons. The characteristics of plasmas are significantly different from those of ordinary neutral gases so that plasmas are considered a distinct "fourth state of matter."
Which statement regarding the effect of humidity on evaporation is correct?- a)With the increase in humidity, rate of evaporation decreases.
- b)Humidity sometimes increases and sometimes decreases the rate of evaporation.
- c)Humidity has no effect on evaporation.
- d)With the decrease in humidity, rate of evaporation decreases.
Correct answer is option 'A'. Can you explain this answer?
Which statement regarding the effect of humidity on evaporation is correct?
a)
With the increase in humidity, rate of evaporation decreases.
b)
Humidity sometimes increases and sometimes decreases the rate of evaporation.
c)
Humidity has no effect on evaporation.
d)
With the decrease in humidity, rate of evaporation decreases.
|
|
Prachi Rathore answered |
in humid air very little evaporation takes place while in dry air Rapid evaporation occurs so wet clothes take longer time to dry in humid air but they dry faster in dry air
What are the characteristics of the particles of matter?
A Particles of matter are in continuous motion
B Particles of matters do not have spaces between them
C Particles of matter attract each other
D Particles of matter are very large in size. - a)(a), (b) and (c) are correct
- b)(a) and (c) are correct
- c)(b) and (c) are correct
- d)All of these
Correct answer is option 'B'. Can you explain this answer?
What are the characteristics of the particles of matter?
A Particles of matter are in continuous motion
B Particles of matters do not have spaces between them
C Particles of matter attract each other
D Particles of matter are very large in size.
A Particles of matter are in continuous motion
B Particles of matters do not have spaces between them
C Particles of matter attract each other
D Particles of matter are very large in size.
a)
(a), (b) and (c) are correct
b)
(a) and (c) are correct
c)
(b) and (c) are correct
d)
All of these
|
|
Vishakha das answered |
The characteristics of particles of matter are as follows:
1. Particles of matter have space between them
When we dissolve salt in water, it is observed that the particles of salt get evenly distributed in water. Also, it is observed that the presence of salt particles did not change the level of water in the beaker. This could be possible only if the particles of salt were accommodated in between the water particles. Thus, this clearly proves that space exists between water particles.
2. Particles of matter are in continuous motion
We know that there is a lot of space present between the particles of matter. Particles of matter are never at rest and keep moving continuously in these free spaces. The particles of matter move continuously and their speed increases with an increase in temperature.
3. Particles of matter attract each other
The particles of matter attract each other. However, this force of attraction varies from matter to matter.
Find the incorrect statement
- a)Low boiling liquids evaporate faster than high boiling liquids.
- b)Cooling is caused during boiling
- c)The normal room temperature is 298K and 293K both.
- d)Evaporation is a surface phenomenon but boiling is not
Correct answer is option 'B'. Can you explain this answer?
Find the incorrect statement
a)
Low boiling liquids evaporate faster than high boiling liquids.
b)
Cooling is caused during boiling
c)
The normal room temperature is 298K and 293K both.
d)
Evaporation is a surface phenomenon but boiling is not
|
|
Raghav Bansal answered |
The normal room temperature is 298K or 25∘C. Other common values are 293 K (20 C or 68 F). Evaporation is a surface phenomenon but boiling is bulk phenomenon. Liquid having low boiling points evaporate faster. Cooling is not caused during boiling.
Match the following with correct response.
(1) Sublimation
(2) Evaporation
(3) Latent heat of vaporization
(4) Latent heat of fusion
(A) Heat required to change the state of 1Kg of solid into liquid
(B) Change of liquid state into vapours without coming to its boiling point
(C) Change of solid directly into vapours
(D) Heat required to change the state of 1Kg liquid into vapours- a)1-D, 2-A, 3-C, 4-B
- b)1-A, 2-C, 3-B, 4-D
- c)1-B, 2-D, 3-A, 4-C
- d)1-C, 2-B, 3-D, 4-A
Correct answer is option 'D'. Can you explain this answer?
Match the following with correct response.
(1) Sublimation
(2) Evaporation
(3) Latent heat of vaporization
(4) Latent heat of fusion
(A) Heat required to change the state of 1Kg of solid into liquid
(B) Change of liquid state into vapours without coming to its boiling point
(C) Change of solid directly into vapours
(D) Heat required to change the state of 1Kg liquid into vapours
(1) Sublimation
(2) Evaporation
(3) Latent heat of vaporization
(4) Latent heat of fusion
(A) Heat required to change the state of 1Kg of solid into liquid
(B) Change of liquid state into vapours without coming to its boiling point
(C) Change of solid directly into vapours
(D) Heat required to change the state of 1Kg liquid into vapours
a)
1-D, 2-A, 3-C, 4-B
b)
1-A, 2-C, 3-B, 4-D
c)
1-B, 2-D, 3-A, 4-C
d)
1-C, 2-B, 3-D, 4-A
|
Pooja Shah answered |
The change of solid directly into vapours is called Sublimation. The change of liquid state into vapours without coming to it's boiling point is called Evaporation. The latent heat of Vaporization is the heat required to change the state of 1 kg into vapours. Latent heat of fusion is the heat required to Change the state of 1 kg of solid into liquid.
The melting point of ice is –- a)0°C
- b)4°C
- c)5°C
- d)None of these
Correct answer is option 'A'. Can you explain this answer?
The melting point of ice is –
a)
0°C
b)
4°C
c)
5°C
d)
None of these
|
Geetika Shah answered |
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. For ice, the melting point is 0°C at which ice a solid turn to water.
Dry ice is –- a)Water in solid state
- b)Water in gaseous state
- c)CO2 in liquid state
- d)CO2 in solid state
Correct answer is option 'D'. Can you explain this answer?
Dry ice is –
a)
Water in solid state
b)
Water in gaseous state
c)
CO2 in liquid state
d)
CO2 in solid state
|
|
Ananya Sharma answered |
Dry ice, sometimes referred to as "cardice", is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue.
Arrange the following substances in increasing order of attraction between the particles: water, sugar, oxygen.- a)water < sugar < oxygen
- b)oxygen < water < sugar
- c)sugar < oxygen < water
- d)none
Correct answer is option 'B'. Can you explain this answer?
Arrange the following substances in increasing order of attraction between the particles: water, sugar, oxygen.
a)
water < sugar < oxygen
b)
oxygen < water < sugar
c)
sugar < oxygen < water
d)
none
|
|
Ravi Verma answered |
Sugar is a solid; the forces of attraction between the particles of sugar are strong. Water is a liquid; the forces of attraction here are weaker than sugar. Oxygen is a gas; the forces of attraction are the weakest in gases.
Thus, the increasing order of forces of attraction between the particles of water, sugar and oxygen is
Oxygen < Water < Sugar
The physical state of matter which can be easily compressed –- a)Liquid
- b)Gas
- c)Solid
- d)None of these
Correct answer is 'B'. Can you explain this answer?
The physical state of matter which can be easily compressed –
a)
Liquid
b)
Gas
c)
Solid
d)
None of these
|
|
Jyoti Kapoor answered |
The physical state of matter which can be easily compressed is the gaseous state as thy have more interparticular space and the particles present in them have very little force of attraction. So they can be easily compressed in contrast to solid and liquid.
Condensing is opposite to evaporating and freezing is opposite to melting.- a)True
- b)False
Correct answer is option 'A'. Can you explain this answer?
Condensing is opposite to evaporating and freezing is opposite to melting.
a)
True
b)
False
|
Tanishq Patel answered |
Explanation:
Condensing and Evaporating:
- Condensing is the process by which a substance changes from a gas to a liquid state, usually by cooling. This occurs when the particles of the gas slow down and come together to form a liquid.
- Evaporating, on the other hand, is the process by which a substance changes from a liquid to a gas state, usually by heating. This occurs when the particles of the liquid gain enough energy to break free and become a gas.
Opposites:
- Condensing and evaporating are indeed opposite processes. When a substance condenses, it goes from a gas to a liquid state, whereas when it evaporates, it goes from a liquid to a gas state. These processes are reverse of each other and involve opposite changes in the state of matter.
Freezing and Melting:
- Freezing is the process by which a substance changes from a liquid to a solid state, usually by cooling. This occurs when the particles of the liquid slow down and come together to form a solid.
- Melting, on the other hand, is the process by which a substance changes from a solid to a liquid state, usually by heating. This occurs when the particles of the solid gain enough energy to break free and become a liquid.
Opposites:
- Freezing and melting are indeed opposite processes. When a substance freezes, it goes from a liquid to a solid state, whereas when it melts, it goes from a solid to a liquid state. These processes are reverse of each other and involve opposite changes in the state of matter.
Condensing and Evaporating:
- Condensing is the process by which a substance changes from a gas to a liquid state, usually by cooling. This occurs when the particles of the gas slow down and come together to form a liquid.
- Evaporating, on the other hand, is the process by which a substance changes from a liquid to a gas state, usually by heating. This occurs when the particles of the liquid gain enough energy to break free and become a gas.
Opposites:
- Condensing and evaporating are indeed opposite processes. When a substance condenses, it goes from a gas to a liquid state, whereas when it evaporates, it goes from a liquid to a gas state. These processes are reverse of each other and involve opposite changes in the state of matter.
Freezing and Melting:
- Freezing is the process by which a substance changes from a liquid to a solid state, usually by cooling. This occurs when the particles of the liquid slow down and come together to form a solid.
- Melting, on the other hand, is the process by which a substance changes from a solid to a liquid state, usually by heating. This occurs when the particles of the solid gain enough energy to break free and become a liquid.
Opposites:
- Freezing and melting are indeed opposite processes. When a substance freezes, it goes from a liquid to a solid state, whereas when it melts, it goes from a solid to a liquid state. These processes are reverse of each other and involve opposite changes in the state of matter.
CO2 can be easily liquified and even solidified because
- a)It has weak forces of attraction
- b)It has a low melting point and low boiling point.
- c)It has more intermolecular space
- d)It is present in atmosphere
Correct answer is option 'B'. Can you explain this answer?
CO2 can be easily liquified and even solidified because
a)
It has weak forces of attraction
b)
It has a low melting point and low boiling point.
c)
It has more intermolecular space
d)
It is present in atmosphere
|
|
Ravi Verma answered |
Carbon dioxide is a gas and has a weak intermolecular force of attraction between its molecules. It can be easily solidified and even liquified because it has a low melting point and low boiling point.
In which one of the following sets is each one a solid under ordinary conditions-- a)Stone, water, ice
- b)Oxygen, Nitrogen, Sulphur
- c)Mercury, Iron, gold
- d)Salt, sugar, chalk
Correct answer is option 'D'. Can you explain this answer?
In which one of the following sets is each one a solid under ordinary conditions-
a)
Stone, water, ice
b)
Oxygen, Nitrogen, Sulphur
c)
Mercury, Iron, gold
d)
Salt, sugar, chalk
|
|
Raghavi Iyer answered |
Solid under Ordinary Conditions
Solid is a state of matter where molecules are closely packed together and have a definite shape and volume. In this question, we have to identify the set of substances that are solids under ordinary conditions.
Salt, Sugar, Chalk
The correct answer is option D, which includes salt, sugar, and chalk. All of these substances are solids at room temperature and atmospheric pressure.
Salt is known as table salt or common salt. It is a crystalline solid that is composed of sodium and chlorine ions. It is used as a seasoning and preservative in food, and also in chemical industries.
Sugar is a sweet-tasting crystalline substance that is found in many plants. It is used as a sweetener in food and drinks. Sugar is also used in the production of ethanol, a type of alcohol used as fuel.
Chalk is a soft, white, porous sedimentary rock that is formed from the accumulation of microscopic marine fossils. It is used in the production of cement, as a filler in products such as paint and rubber, and as a writing tool on blackboards.
Stone, Water, Ice
Option A includes stone, water, and ice. While stone is a solid under ordinary conditions, water and ice are not. Water is a liquid at room temperature and atmospheric pressure, while ice is a solid at temperatures below 0°C.
Oxygen, Nitrogen, Sulphur
Option B includes oxygen, nitrogen, and sulfur. Oxygen and nitrogen are gases at room temperature and atmospheric pressure, while sulfur is a solid. However, sulfur is not a solid under ordinary conditions as it has a melting point of 115°C.
Mercury, Iron, Gold
Option C includes mercury, iron, and gold. Mercury is a liquid at room temperature and atmospheric pressure, while iron and gold are solids. However, mercury is not a solid under ordinary conditions as it has a melting point of -39°C.
Conclusion
In conclusion, the correct answer is option D, which includes salt, sugar, and chalk, as they are all solids under ordinary conditions.
Solid is a state of matter where molecules are closely packed together and have a definite shape and volume. In this question, we have to identify the set of substances that are solids under ordinary conditions.
Salt, Sugar, Chalk
The correct answer is option D, which includes salt, sugar, and chalk. All of these substances are solids at room temperature and atmospheric pressure.
Salt is known as table salt or common salt. It is a crystalline solid that is composed of sodium and chlorine ions. It is used as a seasoning and preservative in food, and also in chemical industries.
Sugar is a sweet-tasting crystalline substance that is found in many plants. It is used as a sweetener in food and drinks. Sugar is also used in the production of ethanol, a type of alcohol used as fuel.
Chalk is a soft, white, porous sedimentary rock that is formed from the accumulation of microscopic marine fossils. It is used in the production of cement, as a filler in products such as paint and rubber, and as a writing tool on blackboards.
Stone, Water, Ice
Option A includes stone, water, and ice. While stone is a solid under ordinary conditions, water and ice are not. Water is a liquid at room temperature and atmospheric pressure, while ice is a solid at temperatures below 0°C.
Oxygen, Nitrogen, Sulphur
Option B includes oxygen, nitrogen, and sulfur. Oxygen and nitrogen are gases at room temperature and atmospheric pressure, while sulfur is a solid. However, sulfur is not a solid under ordinary conditions as it has a melting point of 115°C.
Mercury, Iron, Gold
Option C includes mercury, iron, and gold. Mercury is a liquid at room temperature and atmospheric pressure, while iron and gold are solids. However, mercury is not a solid under ordinary conditions as it has a melting point of -39°C.
Conclusion
In conclusion, the correct answer is option D, which includes salt, sugar, and chalk, as they are all solids under ordinary conditions.
Can you explain the answer of this question below:Particles of matter are continuously moving. What is the effect of rise in temperature on moving particles?
- A:
With rise in temperature, particles move faster
- B:
With rise in temperature, particles stop moving
- C:
With rise in temperature, particles move slowly
- D:
None of the above
The answer is a.
Particles of matter are continuously moving. What is the effect of rise in temperature on moving particles?
With rise in temperature, particles move faster
With rise in temperature, particles stop moving
With rise in temperature, particles move slowly
None of the above
|
|
Suyash Nambiar answered |
Effect of rise in temperature on moving particles
When the temperature of a substance is raised, the kinetic energy of the particles in the substance increases. This increased kinetic energy results in faster movement of the particles. Therefore, option A is correct. The movement of particles increases with an increase in temperature.
The movement of particles is directly proportional to the temperature of the substance. As the temperature of the substance increases, the particles gain more kinetic energy. This energy is utilized by the particles to move faster. Consequently, the increased speed of the particles leads to an increase in the overall energy of the substance.
In conclusion, the effect of rise in temperature on moving particles is that they move faster. This is due to the increased kinetic energy gained by the particles as the temperature of the substance is raised.
- A: With rise in temperature, particles move faster
- B: With rise in temperature, particles stop moving
- C: With rise in temperature, particles move slowly
- D: None of the above
When the temperature of a substance is raised, the kinetic energy of the particles in the substance increases. This increased kinetic energy results in faster movement of the particles. Therefore, option A is correct. The movement of particles increases with an increase in temperature.
The movement of particles is directly proportional to the temperature of the substance. As the temperature of the substance increases, the particles gain more kinetic energy. This energy is utilized by the particles to move faster. Consequently, the increased speed of the particles leads to an increase in the overall energy of the substance.
In conclusion, the effect of rise in temperature on moving particles is that they move faster. This is due to the increased kinetic energy gained by the particles as the temperature of the substance is raised.
Why do naphthalene balls disappear with time without leaving any solid behind?- a)Due to melting
- b)Due to freezing
- c)Due to boiling
- d)Due to sublimation
Correct answer is option 'D'. Can you explain this answer?
Why do naphthalene balls disappear with time without leaving any solid behind?
a)
Due to melting
b)
Due to freezing
c)
Due to boiling
d)
Due to sublimation
|
Aashi answered |
The correct answer is due to sublimation because naphthalene balls are sublime substance therefore the process of sublimation takes place in this process!!
The temperature at which a liquid changes into its gaseous form is called _________.- a)boiling point
- b)melting point
- c)freezing point
- d)triple point
Correct answer is option 'A'. Can you explain this answer?
The temperature at which a liquid changes into its gaseous form is called _________.
a)
boiling point
b)
melting point
c)
freezing point
d)
triple point
|
|
Mainak Yadav answered |
Boiling Point:
The temperature at which a liquid changes into its gaseous form is called the boiling point.
Explanation:
When a liquid is heated, the kinetic energy of its molecules increases. At a certain temperature, the kinetic energy of the molecules becomes sufficient to overcome the intermolecular forces holding the liquid together. At this point, the liquid starts to turn into its gaseous form, which is called vaporization. The temperature at which this happens is called the boiling point.
Factors Affecting Boiling Point:
The boiling point of a liquid depends on various factors such as:
1. Pressure: The boiling point of a liquid decreases with a decrease in pressure and increases with an increase in pressure.
2. Intermolecular Forces: The boiling point of a liquid increases with an increase in intermolecular forces.
3. Molecular Size: The boiling point of a liquid increases with an increase in molecular size.
Importance of Boiling Point:
The boiling point of a liquid is an important physical property used to identify and classify liquids. It also plays a crucial role in various industrial processes such as distillation, fractional distillation, and steam generation.
Conclusion:
In conclusion, the boiling point is the temperature at which a liquid changes into its gaseous form. It depends on various factors such as pressure, intermolecular forces, and molecular size. The boiling point is an important physical property and plays a crucial role in various industrial processes.
The temperature at which a liquid changes into its gaseous form is called the boiling point.
Explanation:
When a liquid is heated, the kinetic energy of its molecules increases. At a certain temperature, the kinetic energy of the molecules becomes sufficient to overcome the intermolecular forces holding the liquid together. At this point, the liquid starts to turn into its gaseous form, which is called vaporization. The temperature at which this happens is called the boiling point.
Factors Affecting Boiling Point:
The boiling point of a liquid depends on various factors such as:
1. Pressure: The boiling point of a liquid decreases with a decrease in pressure and increases with an increase in pressure.
2. Intermolecular Forces: The boiling point of a liquid increases with an increase in intermolecular forces.
3. Molecular Size: The boiling point of a liquid increases with an increase in molecular size.
Importance of Boiling Point:
The boiling point of a liquid is an important physical property used to identify and classify liquids. It also plays a crucial role in various industrial processes such as distillation, fractional distillation, and steam generation.
Conclusion:
In conclusion, the boiling point is the temperature at which a liquid changes into its gaseous form. It depends on various factors such as pressure, intermolecular forces, and molecular size. The boiling point is an important physical property and plays a crucial role in various industrial processes.
Latent heat of fusion is the amount of heat energy required to change:- a)1 kg of solid into its gaseous state at its boiling point
- b)1 kg of liquid into its solid state at its freezing point
- c)1 kg of liquid into its gaseous state at its boiling point
- d)1 kg of solid into its liquid state at its melting point
Correct answer is option 'D'. Can you explain this answer?
Latent heat of fusion is the amount of heat energy required to change:
a)
1 kg of solid into its gaseous state at its boiling point
b)
1 kg of liquid into its solid state at its freezing point
c)
1 kg of liquid into its gaseous state at its boiling point
d)
1 kg of solid into its liquid state at its melting point
|
|
Ravi Verma answered |
The enthalpy of fusion is a latent heat, because during melting the heat energy needed to change the substance from solid to liquid at atmospheric pressure is latent heat of fusion, as the temperature remains constant during the process.
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