120 100 Temperature/°C 99 90 80 60 40 Slope = 0.239 20 20 Slope = 0.501 0 500 Slope = 0.493 1000 1500 2000 2500 3000 3500 -20 Energy required per gram (J/g) Calculate the energy required (in kilojoules) to convert 3.2 kg of liquid water at 25°C into liquid water at 60°C.

It has been determined that the body can generate 5500 kJ of energy during one hour of strenuous exercise. Perspiration is the bodys mechanism for eliminating this heat. What mass of water would have to be evaporated through perspiration to rid the body of the heat generated during 2 hours of exercise? (The heat of vaporization of water is 40.6 kJ/mol.)

If 14.5 kJ of heat were added to 485 g of liquid water, how much would its temperature increase?

How much heat is evolved when 1255 g of water condensesto a liquid at 100°C?

Differentiate between the enthalpy of formation of H2O(l)andH2O(g) . Why is it necessary to specify thephysical state of water in the following thermochemicalequation CH4(g)+2O2(g)CO2(g)+2H2O(lorg)H=?

The temperature of the cooling water as it leaves the hot engine of an automobile is 240 F. After it passes through the radiator it has a temperature of 175 F. Calculate the amount of heat transferred from the engine to the surroundings by one gallon of water with a specific heat of 4.184 J/g oC.

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?

What is the change in internal energy when a gas contracts from 377mL to 119mLundera pressure of 1550 torr, whileat the same time being cooled by removing 124.0J ofheat energy?

A student is asked to calculate the amount of heat involved in changing 10.0 g of liquid bromine at room temperature (22.5C) to vapor at 59.0C.To do this, one must use Tables 8.1 and 8.2 for information on the specific heat, boiling point, and heat of vaporization of bromine. In addition, the following step-wise process must be followed. (a) Calculate H for: Br2(l,22.5C)Br2(l,59.0C) (b) Calculate H for: Br2(l,59.0C)Br2(g,59.0C) (c) Using Hess's law, calculate H for: Br2(l,22.5C)Br2(g,59.0C)

Suppose you wanted to cool 100. g of water from 20 C to 0 C using dry ice, CO2(s). The enthalpy of sublimation of CO2(s) is 25.2 kJ/mol. What mass of dry ice should you need? (a) 033 g (b) 15 g (c) 3.5 g (d) 150 g