specific heat capacity and Latent heat

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KLQ: What is specific latent heat?

Multiple Choice

Which of the following is measured in joules?

• Temperature

• Heat

• Mass

• Volume

Open Ended

Why is understanding the relationship between heat and temperature important in everyday life?

Open Ended

How much energy is stored in hot water?

Multiple Choice

What is the definition of specific heat capacity?

• The amount of energy needed to raise the temperature of 1 kilogram of a substance by 1°C

• The amount of energy needed to melt 1 kilogram of a substance

• The amount of energy needed to freeze 1 kilogram of a substance

• The amount of energy needed to evaporate 1 kilogram of a substance

Multiple Choice

Which of the following variables are required to calculate the change in thermal energy using the equation ΔE = m c Δθ?

• Mass, specific heat capacity, temperature change

• Volume, specific heat capacity, temperature change

• Mass, density, temperature change

• Mass, specific heat capacity, pressure change

Multiple Choice

A mass of 2.0 kg of water is heated. The temperature increase of the water is 80°C. The specific heat capacity of water is 4200 J/kg°C. Calculate the change in thermal energy when the water is heated. Use the equation: ΔE = m c Δθ

• 678000 J

• 668000 J

• 896456 J

• 768000 J

Multiple Choice

A 1.5 kg container of water is heated from 25°C to 35°C. The specific heat capacity of water is 4200 J/kg°C. How much thermal energy was transferred to the water? Use equation: ΔE = m c Δθ

• 1340000 J

• 2, 140, 000 J

• 1,130,000 J

• 1230 000 J

Multiple Choice

A 3 kg liquid is heated from 18°C to 38°C. 75,600 J of thermal energy is supplied. Find the specific heat capacity. Use the equation: ΔE = m c Δθ. Hint: We need to find c, so rearrange the equation.

• 2260

• 60

• 12600

• 1260

Multiple Choice

What is latent heat?

• The energy required to change the state of a substance without changing its temperature.

• The energy required to increase the temperature of a substance.

• The energy released when a substance cools down.

• The energy needed to break chemical bonds in a reaction.

Multiple Choice

Explain the difference between latent heat and specific latent heat.

• Specific latent heat is the energy absorbed or released during a phase change, while latent heat is the energy per unit mass required for the phase change.

• latent heat is the energy absorbed or released during a phase change, while specific latent heat is the energy per unit mass required for the phase change.

• There is no difference

• latent heat is the energy wasted during a phase change, while specific latent heat is the energy per unit mass required for the phase change.

Multiple Choice

During which parts of the heating curve does the temperature remain constant, and what process is occurring at these points?

• During melting and boiling, when a change of state occurs.

• During the entire heating process, as heat is absorbed.

• Only when the substance is in the liquid state.

• Only at the beginning of the heating curve.

Multiple Choice

Which of the following statements about specific latent heat of fusion is correct?

• It is the energy needed to change 1 kg of a substance from solid to liquid without changing its temperature.

• It is the energy needed to change 1 kg of a substance from liquid to gas without changing its temperature.

• It is the energy required to increase the temperature of 1 kg of a substance by 1°C.

• It is the energy released when 1 kg of a substance freezes.

Fill in the Blanks

Fill in the blank: The equation for energy required for a change of state is E =

× L.

Multiple Choice

1.How much energy is needed to melt 2 kg of ice at 0°C?
(Specific latent heat of fusion of ice = 334,000 J/kg)

• 668 000 J

• 768 00 J

• 100 680 J

• 668 000 KJ

Open Ended

How much energy is required to boil 0.5 kg of water at 100°C? Specific latent heat of vaporization of water = 2,260,000 J/kg.

Multiple Choice

Which of the following statements correctly describes the difference between specific latent heat of fusion and specific latent heat of vaporization?

• Latent heat of fusion is the energy required to change a substance from solid to liquid, while latent heat of vaporization is the energy required to change a substance from liquid to gas.

• Latent heat of fusion is the energy required to change a substance from liquid to gas, while latent heat of vaporization is the energy required to change a substance from solid to liquid.

• Both latent heat of fusion and vaporization refer to the energy required to change a substance from solid to gas.

• Latent heat of fusion and vaporization are not related to phase changes.

Multiple Choice

How are heat and temperature related?

• When we add heat (energy), the temperature of the object rises.

• Heat and temperature are not related.

• Temperature decreases when heat is added.

• Heat is only present in solids.