<p>1. Find the heat lost when a metal object with a C of 0.833 J/g°C, and a mass of 125 g is cooled from 285.0°C to 150.0°C.</p><p>2. How much heat is needed to raise a 265 g sample of gold from 23.0°C to its melting point of 1064°C (Cgold = 0.128 J/g°C)</p><p>3. What is the total heat change when a germanium microchip with a mass of 0.0151 g is heated from 55.2°C to 376.0°C? (CGe = 0.322 J/g°C)</p><p>4. Find the specific heat of a material if 12.5 g gives up 437 J of heat as it cools from 83.1°C to 30.6°C.</p><p>5. If 14.4 g of a liquid requires 815 J of heat to raise its temperature from 20.0°C to 43.1°C, what is the specific heat of the liquid?</p><p>6. Calculate the heat necessary to change the temperature of one kg of iron from 25C to 1000C. The specific heat of iron is 0.451 J/gC. 7. How many joules are required to heat 100. g of Cu from 10.0°C to 100.0°C? (CCu = 0.386 J/gC)</p><p>8. How much heat, in J, is released when 100.0 g of water cools from 38.5°C to 21.3°C?</p><p>9. Which requires more heat to warm from 22C to 85C, 50.0 g of water or 200. g of </p><p> aluminum metal? CAl = 0.902 J/gC</p><p>10. How much energy must be absorbed by 50.0 g of water to raise its temperature from 22.5 to 54.5 °C?</p><p>11.The specific heat capacity of iron is 0.108 cal/g°C. How many calories are required to raise the temperature of an iron nail (8.25 g) from 23.5°C to 95.0 °C?</p><p>12. If 3345 J of heat is supplied to a 75.0 g sample of water at room temperature (23.0°C), what will the final temperature of the water be? </p><p>13. If 75.0 cal are required to raise the temperature of a 12.3 g piece of metal from 22.6°C to 88.3°C, what is the specific heat capacity of the metal? 14. Suppose you consumed five glasses (250. g each) of ice water (0°C) on a hot summer day. If your body temperature is 37°C, how many calories of heat energy will your body supply to warm this water to body temperature?</p><p>15.A diet drink has an energy content of only 6.0 “Cal”. How many grams of room temperature (22.0°C) water could be heated to boiling (100.0°C) with this amount of heat energy?</p><p>16.A small box of raisins provides 120. Kcal of heat energy. If this energy were used to raise the temperature of room temperature (22.0 °C) water to boiling, how many mL of water could be boiled by the raisins?</p><p>17.When 182 g of gold at some temperature is added to 22.1 g of water at a temperature of 25.0 C, the final temperature of the system is 27.5C. If the specific heat is gold is 0.128 J/gC, what was the initial temperature of the gold sample?</p><p>18. When 40 grams of ammonium nitrate is dissolved in 100 grams of water in a constant-pressure coffee-cup calorimeter, the temperature of the solution drops by 22.4C. If the specific heat capacity of the solution is 4.18 J/gC, calculate the heat absorbed by the dissolving of ammonium nitrate.</p><p>19. A block of lead (mass 30 grams; C = 0.128 J/gC) at 90.0C is dropped into water at 20.0C in a well-insulated coffee-cup calorimeter. The final temperature of the system is 21.6C. What volume of water was in the calorimeter? 20. Assume you place 100. g each of copper and gold, each originally at 25C, in a boiling water bath at 100C. If each metal takes up heat at the same rate (the number of joules of heat absorbed per minute is the same), which piece of metal reaches 100C first? Why? </p><p>21.Suppose you want to heat the air in your house with natural gas methane, CH4). Assume your house has 275 m2 (about 2800 ft2) of floor area and that the ceilings are 2.50 m from the floors. The air in the house has a specific heat capacity of 1.01 J/gC and a density of 1.22 g/L. How much methane do you have to burn to heat the air from 15.0 C to 22.0C, knowing that each gram of methane releases 0.01999 kJ of energy when burned?</p><p>22. Two iron bolts of equal mass—one at 100C, the other at 55C—are placed in an insulated container. Assuming the heat capacity of the container to be negligible. </p><p>What is the final temperature inside the container? (Ciron = 0.450 J/gC)</p><p>23. One piece of copper jewelry at 100C has exactly twice the mass of another piece, which is at 40C. They are placed inside a calorimeter whose heat capacity is </p><p> negligible. What is the final temperature inside the calorimeter? (Ccopper = 0.387 J/gC)</p><p>24. Water has a particularly high specific heat capacity. Explain why citrus growers in Florida spray their orchards with water when frost is predicted. </p><p>25. Typically, when you eat a meal, your body metabolizes the food over time. What if this were not the case? What if whatever you ate was converted immediately to heat? How would this impact your body temperature. Assume you have a mass of 65 kg and eat a 400 Calorie breakfast, what would be your body temperature if the energy were all converted to heat? (Assume a starting body temperature of 98.6 F, and that, for simplicity’s sake, you are 100% water). Would you be able to survive the meal? </p><p>26. A 20.0 g sample of a candy bar is burned in a bomb calorimeter. The calorimeter contains 2225 mL of water and the temperature of the water rises from 19.5 to 58.9°C. How many food “Cal” would be in the whole candy bar (60.0 g)?</p><p>27. A blacksmith heated an iron bar to 1445°C. The blacksmith then tempered the metal by dropping it into 25 L of water that had a temperature of 21°C. The final temperature of the system was 52°C. If iron has a specific heat capacity of 0.45 J/g°C, what was the mass of the iron bar?</p><p>28. A piece of an unknown metal with a mass of 21.7 g is heated to 100.0°C and dropped into 50.0 mL of water at 23.6°C. The final temperature of the system is 32.5 °C. What is the specific heat capacity of the metal? 29. A geologist at a mining company is trying to identify a metal sample obtained from an ore. The metal has a mass of 5.05 g and is heated to 100.00°C. The hot metal is dropped into 10.00 mL of water at 22.00°C. The final temp of the system is 23.83°C. What is the specific heat capacity of the metal?</p><p>30.A commercial product called “Instant Car Kooler” contains 10% by weight ethanol, C2H5OH, and 90% by weight water. If the interior of your car is overheated, you spray the “Kooler” inside and the interior is cooled. It works because thermal energy must be transferred to the alcohol and water from the warm air. To drop the air temperature from 55C to 25C requires air to give up 3.6 kJ. How many grams of the ethanol-water mixture must be used to absorb this heat? (The enthalpy of vaporization for ethanol is 850 J/g and for water it is 2360 J/g.)</p>