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WorksheetsMatter in Our Surrounding_3
Total questions: 25
Worksheet time: 1hrs 26mins
Latent heat is
the heat absorbed or released at a boiling process during a change of phase
the heat absorbed or released at a constant temperature during a change of phase
the heat absorbed or released at a constant temperature during a change of phase of 1 kg object
the heat absorbed or released by an object to increase or decrease its temperature by 1 degree Celcius
The heat absorbed by melting a solid is known as
latent heat of fusion
latent heat of solid
latent heat of liquid
latent heat of vaporisation
specific latent heat of vaporisation is
the amount of heat required to change 1 kg of the substance from the solid to liquid phase without change in temperature
the amount of heat required to change 1 kg of the substance from the liquid to gaseous phase without change in temperature
the amount of heat required to change the temperature 1 kg of the substance by 1 degree Celcius
Specific latent heat of fusion is the quantity of (a) that is absorbed during melting of 1 kg of a substance without any change in temperature.
If the temperature is below the melting point of a substance and below the boiling point of a substance what state will it be in?
Solid
Liquid
Gas
If the temperature is above the melting point of a substance and above the boiling point of a substance what state will it be in?
Solid
Liquid
Gas
A substance has a melting point of 25 oC and a boiling point of 235 oC. What state is it at 5oC?
Solid
Liquid
Gas
A substance has a melting point of -125 oC and a boiling point of -35 oC. What state is it at 15oC?
Solid
Liquid
Gas
A substance has a melting point of -25 oC and a boiling point of 35 oC. What state is it at 25oC?
Solid
Liquid
Gas
Latent Heat
At the end of this session, you will be able to:
Describe change of phases of matter
Explain different phases of matter and transition between them
Describe latent heat of fusion and latent heat of vaporization
Change of phases of matter:
Nearly every substance exists as a solid, liquid, or gaseous state. An ice cube turns into water when left out of the freezer. A vessel of water will turn into ice if it is left in the freezer. And water boils out of your pot if it is heated for too long.
Thus, when water is frozen, it solidifies to ice, and when heated for too long, it evaporates into steam. Ice, water, and steam are three phases of matter of the same substance, water.
Why is understanding latent heat crucial for comprehending transitions between different phases of matter?
It helps in predicting the amount of energy required for phase changes
It determines the temperature at which phase transitions occur
It affects the density of the material during phase changes
It influences the color of the substance in different phases
What topics are covered in the video and text content?
Thermodynamics
Quantum Mechanics
Latent heat, phase transitions, and properties of different phases of matter
Electromagnetism
What are the session objectives related to phases of matter and latent heat?
Describing the change of phases of matter
Explaining different phases of matter and transitions between them
Describing latent heat of fusion and vaporization
None of the above
What are examples of phase changes mentioned in the text?
Melting and freezing
Boiling and condensation
Sublimation and deposition
Evaporation and precipitation
What are the three phases of matter that water showcases?
Solid, liquid, gas
Solid, gas, plasma
Liquid, gas, plasma
Solid, liquid, plasma
What are the different states in which substances exist?
Solid, liquid, gas
Solid, gas, plasma
Liquid, gas, plasma
Solid, liquid, plasma
What concepts does the content focus on?
Thermodynamics
Electricity
Magnetism
Gravity
What happens to water when it is heated for too long?
What state does water turn into when it is frozen?
What is the gaseous state of water called?
What state of matter is ice?
Ice turns into water when it is heated. (True/False)
Water solidifies into ice when it is heated for too long. (True/False)
Water turns into ______ when left in the freezer.
When heated, water evaporates into ______.
Which of the following is not a phase of matter?
The process of a solid turning directly into a gas is called:
What is the process called when a liquid turns into a gas?
What is the process called when a gas turns into a liquid?
Melting is the process of a solid turning into a liquid. (True/False)
True
False
Condensation is the process of a liquid turning into a gas. (True/False)
Match
Solid to Liquid
Melting
Liquid to Gas
Evaporation
Gas to Liquid
Condensation
Solid to Gas
Sublimation
When a liquid turns into a solid, the process is called ______.
freezing
The phase transition from solid to liquid is known as ______.
What is latent heat of fusion?
The latent heat of vaporization is the heat required to:
The latent heat of vaporization is the heat required to:
What is the heat required to melt a solid called?
What is the heat required to vaporize a liquid called?
Latent heat of fusion is the heat required to change a solid into a liquid at its melting point. (true/false)
Latent heat of vaporization is the heat required to change a liquid into a gas at its boiling point. (True/False)
Latent Heat of Fusion
Melting a Solid
Vaporizing a Liquid
Latent Heat of Vaporization
Melting a Solid
Vaporizing a Liquid
The ______ heat of fusion is the heat required to change a solid into a liquid.
The ______ heat of vaporization is the heat required to change a liquid into a gas.
Explaining the process involved in change of phases:
A continuous supply of heat to a mass of ice converts it to liquid and then to steam. The mass of ice absorbs heat energy and melts into water. This change of state from solid ice to liquid water is termed as fusion. Water absorbs heat when heated for a few minutes and eventually vaporizes. This change of state from water to steam is called vaporization. Vaporization of a matter is a process of phase transition from liquid to gaseous state.
Furthermore, steam releases its heat and converts into water droplets when collected in a vessel. The process of transiting phase from steam into water is termed as condensation. Condensation is the change of physical state of matter from its gaseous phase into liquid phase.
What is vaporization?
Solid to liquid transition
Liquid to gaseous transition
Gas to solid transition
Liquid to solid transition
What is condensation?
Solid to liquid phase change
Gaseous to liquid phase change
Liquid to gaseous phase change
Liquid to solid phase change
What is the change from water to steam called?
Condensation
Freezing
Vaporization
Melting
What happens when continuous heat supply is applied to ice?
It converts to liquid
It converts to steam
It remains solid
It evaporates
What is fusion?
Change from liquid water to solid ice
Change from solid ice to liquid water
Change from liquid water to gas
Change from gas to liquid water
What happens when water absorbs heat?
It freezes
It vaporizes
It solidifies
It condenses
What happens when steam is collected?
It evaporates into the air
It condenses into water droplets
It turns into ice crystals
It remains in its gaseous state
What is the process called when ice absorbs heat and converts to liquid water?
What happens to water when it absorbs heat for a few minutes?
What is the term for the change of state from liquid to gaseous?
When steam releases heat and converts into water droplets, what is this process called?
What is the process called when ice changes to liquid water?
Fusion
What is the process called when liquid water changes to steam?
What is the process called when steam changes to water?
What is the process called when steam changes to water?
Fusion is the process of converting liquid water into steam. (True/False)
Vaporization is the process of converting ice into water. (True /False)
Condensation is the process of converting gaseous steam into liquid water. (True/False)
Match the following
Ice to Water
Fusion
Water to Steam
Vaporization
Steam to Water
Condensation
A continuous supply of heat to a mass of ice converts it to ______ and then to ______.
The change of state from solid ice to liquid water is termed as ______.
The process of changing from liquid water to steam is called ______.
The process of transiting phase from steam into water is termed as ______.
Temperature of the system remains constant during phase change. During phase change, temperature remains constant even though heat is absorbed or released by the substance.
Let's illustrate this:
When ice melts to water and changes to steam by heating, place a thermometer in the vessel containing ice and gradually heat the vessel over a low flame. The temperature of the ice vessel remains constant at zero degree Celsius till all ice has melted. In spite of supplying heat to ice, its temperature remains constant. This fixed temperature at which a solid ice cube melts to liquid water is called melting point.
The fixed temperature starts rising after the ice in the vessel is melted to water. Rise of temperature level stops again at 100 degree Celsius when water starts boiling. As water boils and vaporizes, the temperature level remains fixed at 100 degree Celsius. This fixed temperature at which liquid boils and changes into steam is called boiling point.
What happens to the temperature during a phase change?
Increases
Decreases
Remains constant
Fluctuates
What happens to the temperature after ice melts and stops at boiling point?
It decreases continuously
It remains constant
It increases continuously
It fluctuates
What happens when ice melts to water and changes to steam?
It turns into a solid
It turns into a gas
It turns into a liquid
It turns into a plasma
At what temperature does ice melt to water?
0°C
100°C
50°C
25°C
At what point does water change into steam?
0°C
100°C
50°C
200°C
Is heat absorbed or released during phase change?
Absorbed
Released
No change
Cannot be determined
What happens to the thermometer when placed in a vessel during a phase change?
It remains constant
It decreases
It increases
It fluctuates
What happens to the temperature of a substance during a phase change?
What is the fixed temperature called at which solid ice melts to liquid water?
0 degrees Celsius or 32 degrees Fahrenheit
Melting point
100 degrees Celsius or 212 degrees Fahrenheit. Boiling Point
50 degrees Celsius or 122 degrees Fahrenheit. Melting Point
10 degrees Celsius or 50 degrees Fahrenheit. Boiling point
At what temperature does water start to boil and change into steam?
At what temperature does water start to boil and change into steam?
What remains constant during a phase change even though heat is absorbed or released?
What is the temperature at which liquid boils and changes into steam called?
The temperature of ice increases continuously as it melts to water. (True/False)
True
The boiling point of water is 100 degrees Celsius. (True/False)
Match the column
Ice melts to water
0 degrees Celsius
Water boils and changes to steam
100 degrees Celsius
Temperature during phase change
Constant
During phase change, the temperature remains ______ even though heat is absorbed or released
The fixed temperature at which solid ice melts to liquid water is called the ______ point.
The fixed temperature at which liquid water boils and changes into steam is called the ______ point.
The temperature of the ice vessel remains constant at ______ degrees Celsius till all ice has melted.
The rise of temperature stops again at ______ degrees Celsius when water starts boiling.
Explaining what latent heat is:
Heat is continuously supplied to ice, but its temperature remains constant at zero degree Celsius till ice melts to water. Similarly, temperature of water remains fixed at its 100 degree Celsius during its change of state to vapor, in spite of continuous supply of heat to it.
This hidden heat supplied to water, which does not affect its temperature level at zero degree Celsius and 100 degree Celsius respectively, during its phase transition, is called latent heat. Latent heat is denoted by L. The unit of latent heat is joules per kilogram.
What happens to latent heat if it does not rise the temperature?
In ice cubes, molecules are tightly bounded by strong forces and vibrate in their confined positions. The vibrations increase on heating, and the molecules collide with each other, and space between the molecules increases. Consequently, ice melts to water by the continuous supply of latent heat by keeping its temperature constant at zero degree Celsius.
The quantity of heat required to convert one kilogram of ice to water without changing its temperature is called latent heat of fusion of ice.
What effect does the continuous supply of latent heat have on ice?
Causes it to freeze
Causes it to evaporate
Causes it to melt to water while keeping its temperature constant at zero degree Celsius
Causes it to solidify
What is the quantity of heat required to convert one kilogram of ice to water without changing its temperature called?
Specific heat of ice
Latent heat of fusion of ice
Heat capacity of water
Thermal conductivity of ice
What is the symbol for latent heat and its unit?
A. M, joules per kilogram
B. L, watts per second
C. Q, joules per kilogram
D. H, watts per second
What happens to the space between molecules in ice cubes when they are heated?
It decreases
It remains the same
It increases
It becomes solid
What is latent heat in relation to water during phase transition?
Heat that affects the temperature level of water
Heat that is visible during phase transition
Heat that is released during phase transition
Heat that does not affect the temperature level of water
What is latent heat?
What is the unit of latent heat?
During the phase change from ice to water, what happens to the temperature when latent heat is supplied?
What is the symbol for latent heat?
What is the latent heat of fusion?
Latent heat affects the temperature of a substance during a phase change. (True/False)
The temperature of ice increases as it melts to water due to latent heat. (True/False)
The unit of latent heat is joules per kilogram. (True/False)
Match the following
Latent heat of fusion of ice
Melting of ice
Temperature during phase change
Constant
Unit of latent heat
Joules per kilogram
Latent heat is the ______ heat supplied during phase transitions that does not change temperature.
hidden
The quantity of heat required to convert one kilogram of ice to water without changing its temperature is called ______ heat of fusion of ice
In ice cubes, molecules are tightly bounded by strong forces and vibrate in their confined positions. The vibrations ______ on heating, causing the molecules to collide and increase the space between them.
The temperature of water remains fixed at ______ degrees Celsius during its change of state to vapor.
The unit of latent heat is ______ per kilogram.
Likewise, temperature of water remains constant at 100 degrees Celsius when it boils and eventually vaporizes, irrespective of continuous supply of heat. As water can only reach a high point of 100 degrees Celsius, this latent heat supply to water sets its molecules free by breaking their intermolecular bonds without affecting their vibrating speed. Consequently, water boils and converts into steam as its boiling point.
The amount of heat required to change one kilogram of liquid water to vapor state at constant temperature is called its latent heat of vaporization.
Importance of latent heat in real life:
Food cooks faster in a closed pan compared to an open pan. This is because the lid of the pan does not allow its produced steam to escape. As latent heat of steam is higher than latent heat of an equal amount of boiled water, steam gives out more heat to cook food inside the closed pan.-
Why does steam give out more heat than an equal amount of boiled water?
Due to its higher boiling point
Due to its lower latent heat
Due to its lower specific heat
Due to its higher latent heat
How does latent heat affect water molecules?
It increases their vibrating speed
It breaks their intermolecular bonds
It decreases their temperature
It changes their chemical composition
How does the lid of a closed pan help in cooking food?
Traps steam to give out more heat
Prevents heat from reaching the food
Allows steam to escape, reducing heat
Has no effect on cooking
What is the temperature of water when it boils and vaporizes?
0 degrees Celsius
50 degrees Celsius
100 degrees Celsius
150 degrees Celsius
What is latent heat of vaporization?
Heat required to change solid water to vapor at constant temperature
Heat required to change liquid water to ice at constant temperature
Heat required to change liquid water to vapor at constant temperature
Heat required to change ice to liquid water at constant temperature
Why does water boil and convert into steam at 100 degrees Celsius?
Due to the supply of latent heat
Due to the lack of oxygen
Due to the presence of impurities
Due to the high pressure
Why does food cook faster in a closed pan compared to an open pan?
Due to the higher boiling point of water in a closed pan
Due to the lower latent heat of steam in a closed pan
Due to the higher specific heat capacity of steam in a closed pan
Due to the higher latent heat of steam in a closed pan
At what temperature does water remain constant when it boils and vaporizes?
What is the latent heat of vaporization?
The amount of heat required to change one kilogram of liquid water to vapor state at constant temperature
Why does food cook faster in a closed pan compared to an open pan?
The closed pan does not allow steam to escape, and steam has a higher latent heat than water
What happens to the temperature of water at its boiling point, despite continuous heating?
What happens to the temperature of water at its boiling point, despite continuous heating?
What is the process called when liquid water changes to steam?
What is the amount of heat required to change one kilogram of liquid water to vapor state called?
The temperature of water increases continuously as it boils. (True/False)
The latent heat of vaporization is the amount of heat required to change one kilogram of liquid water to vapor state at constant temperature. (True/False)
Food cooks faster in an open pan compared to a closed pan. (True/False)
Match the following
Latent heat of vaporization
Boiling of water
Temperature during boiling
100 degrees Celsius
Reason for faster cooking in a closed pan
Higher latent heat of steam
The temperature of water remains constant at ______ degrees Celsius when it boils and eventually vaporizes, irrespective of continuous supply of heat.
The latent heat supply to water breaks the ________ bonds between molecules without affecting their vibrating speed.
intermolecular
The amount of heat required to change one kilogram of liquid water to vapor state at constant temperature is called its latent heat of _________
Food cooks faster in a ______ pan compared to an open pan because the lid does not
allow the steam to escape.
As latent heat of steam is higher than latent heat of an equal amount of boiled water, steam gives out more heat to ______ food inside the closed pan.
