Molecular Physics | Thermodynamics Answers

Find the weight density of a block 7 in. x 5.5 in. x 9 in. that weighs 65 lb. Express your

answer to four decimal places.

How much heat is required to heat a 540g of iron from 300c to 65°c?

What is the specific heat capacity if it takes 1000 J of energy to heat 25 g of this substance by 100°C? Give your answer in J/kg°C.

A box with a total surface area of 0.83 m2

and

a wall thickness of 2.72 cm is made of an insulating material. A 11.8 W electric heater

inside the box maintains the inside temperature at 7.4

◦C above the outside temperature.

Find the thermal conductivity of the insulating material.

Answer in units of W/m · ◦ C.

One liter of water at 43◦C is used to make iced

tea.

How much ice at 0 ◦C must be added to

lower the temperature of the tea to 14 ◦C?

The specific heat of water is 1 cal/g · ◦ C and

latent heat of ice is 79.7 cal/g.

Answer in units of g.

How much energy is required to change a 44 g

ice cube from ice at −13◦C to steam at 111◦C?

The specific heat of ice is 2090 J/kg · ◦ C, the

specific heat of water is 4186 J/kg · ◦ C, the

specific heat of stream is 2010 J/kg · ◦ C, the

heat of fusion is 3.33 × 105

J/kg, and the heat

of vaporization is 2.26 × 106 J/kg.

Answer in units of J.

A jar of tea is placed in sunlight until it

reaches an equilibrium temperature of 33.4◦C .

In an attempt to cool the liquid, which has a

mass of 184 g , 103 g of ice at 0.0◦C is added.

At the time at which the temperature of the

tea is 32.6◦C , find the mass of the remaining ice in the jar. The specific heat of water

is 4186 J/kg ·◦ C . Assume the specific heat

capacity of the tea to be that of pure liquid

water.

Answer in units of g.

A 0.0625 kg ingot of metal is heated to 213◦C

and then is dropped into a beaker containing

0.4 kg of water initially at 20◦C.

If the final equilibrium state of the mixed

system is 22.4◦C, find the specific heat of

the metal. The specific heat of water is

4186 J/kg ·◦ C.

Answer in units of J/kg ·◦ C.

A 300 g glass thermometer initially at 21 ◦C

is put into 247 cm3

of hot water at 81 ◦C.

Find the final temperature of the thermometer, assuming no heat flows to the

surroundings. The specific heat of glass is

0.2 cal/g · ◦ C and of water 1 cal/g · ◦ C.

Calculate the specific heat capacity of a 3.0kg piece of metal which experiences a temperature rise of 25∘C when it is heated at a rate of 60W for 10minutes, if a total of 3000J heats the surroundings during this process.