South Pasadena AP Chemistry s10

Honors Chemistry PS.40 Name: ______Date: ______Mods: ______

Unit 10: Specific Heat & Calorimetry

1) If a 50.0 g piece of glass was initially at 20°C, what will be the final temperature if the glass absorbs 5.275 kilojoules of heat and has a specific heat of 0.50 J/g°C?

2) Calculate the heat capacity of a piece of wood if 1500.0 g of the wood absorbs 6.75×104 joules of heat, and its temperature changes from 32°C to 57°C.

3) 100.0 mL of 4.0°C water is heated until its temperature is 37°C. If the specific heat of water is 4.184 J/g°C, calculate the amount of heat energy needed to cause this rise in temperature.

4) If 55 calories of heat were needed to raise the temperature of ice from – 58oC up to – 29oC, what must have been the mass of ice sample that was heated? The specific heat of ice is 2.108 J/g°C.

5) What is the specific heat capacity of silver metal if 55.00 g of the metal absorbs 47.3 calories of heat and the temperature rises 15.0°C?

6) The specific heat of iron is 0.46 J/g.°C. If 13.8 kJ of heat is applied to a 324 g piece of iron, what will be the temperature change for the sample? 7) Supose you have two separates samples: 5.00 grams of ethanol (Cp of C2H5OH = 2.44 J/g°C ) and 5.00 grams of water. Both the ethanol and the water initially start at the same temperature of 10.0°C. If each sample is individually heated with 300 J of energy, determine the final temperature of the water sample and the final temperature of the ethanol sample. How does the specific heat of each sample affect their final temperatures when the same quantity of heat was added?

8) 50.0 g of iron that has an initial temperature of 225 ºC and 50.0 g of gold that has an initial temperature of 25.0 ºC are brought into contact with one another. Assuming no heat is lost to the surroundings, what will be the final temperature when the two metals reach a thermal equilibrium? (specific heat capacity of iron = 0.499 J/gºC and gold = 0.128 J/gºC)

9) A 14.7 g sample of a metal alloy is heated to 96.8 ºC and then dropped into 20 g of water in a calorimeter. The temperature of the water rises from 22 ºC to 24.1 ºC. What is the specific heat of the metal? 10) 175 grams of hot aluminum (100ºC) is dropped into an insulated cup that contains 40.0 g of ice cold water (0.0ºC). Determine the final temperature, TF, if the heat capacity of water is 4.184 J/gºC. The specific heat of aluminum is 0.90 J/gºC.

11) A 15.5 g sample of a metal alloy is heated to 98.9°C and then dropped into 25.0 g of water in a calorimeter. The temperature of the water rises from 22.5°C to 25.7°C. What is the specific heat of the metal alloy?