What is the temperature of vaporization, Tvapor, of the substance? Given a 80.2-g sample of this substance with a specific heat of 56.9 J/(kg.°C), how much heat is required to change its temperature from 180.0 °C to 220.0 °C? Tvapor 280 Correct Answer °C 207.9 Q= J Incorrect Answer

A 110.-g sample of copper (specific heat capacity = 0.20 J/C g) is heated to 82.4C and then placed in a container of water at 22.3C. The final temperature of the water and copper is 24.9C. What is the mass of the water in the container, assuming that all the heat lost by the copper is gained by the water?

Equal masses of liquid A, initially at 100C, and liquid B, initially at 50C, are combined in an insulated container. The final temperature of the mixture is 80C. All the heat flow occurs between the two liquids. The two liquids do not react with each other. Is the specific heat of liquid A larger than, equal to, or smaller than the specific heat of liquid B?

9.45 What happens to the temperature of a material as it undergoes an endothermic phase change? If heat is added, how can the temperature behave in this manner?

You wish to heat water to make coffee. How much heat (in joules) must be used to raise the temperature of 0.180 kg of tap water (enough for one cup of coffee) from 30C to 96C (near the ideal brewing temperature)? Assume the specific heat is that of pure water, 4.18 J/(gC).

How much heat, in joules and in calories, must be added to a 75.0g iron block with a specific heat of 0.449 Jig C to increase its temperature from 25 C to its melting temperature of 1535 C?

Quinone is an important type of molecule that is involved in photosynthesis. The transport of electrons mediated by quinone in certain enzymes allows plants to take water, carbondioxide, and the energy of sunlight to create glucose. A 0.1964-g sample of quinone (C6H4O2) is burned in a bomb calorimeter with a heat capacity of 1.56 kJ/C. The temperature of the calorimeter increases by 3.2C. Calculate the energy of combustion of quinone per gram and per mole.

You have two samples of different metals, metal A and metal B, each having the same mass. You heat both metals to 95C and then place each one into separate beakers containing the same quantity of water at 25C. a You measure the temperatures of the water in the two beakers when each metal has cooled by 10C and find that the temperature of the water with metal A is higher than the temperature of the water with metal B. Which metal has the greater specific heat? Explain. b After waiting a period of time, the temperature of the water in each beaker rises to a maximum value. In which beaker does the water temperature rise to the higher value, the one with metal A or the one with metal B? Explain.

The “Chemistry in Focus” segment Nature Has Hot Plants discusses thermogenic, or heat-producing, plants. For some plants, enough heat is generated to increase the temperature of the blossom by 15 °C. About how much heat is required to increase the temperature of 1 L of water by 15 °C?

Copper is used in building the integrated circuits, chips, and printed circuit boards for computers. When 228 J of heat are absorbed by 125 g of copper at 22.38C, the temperature rises to 27.12C. What is the specific heat of copper?