9 = MCAT 3. How much energy is needed to change the temperature of 50.0 g of water by 15.0 C? Leave your answer in joules. 91 = ( 50g) ( 4.184 (8) ) ( 152) M = 50 g C = 4.189 ? AT 15 5 ge 9= 3.14 X 103 5 4. How much heat in kJ must be removed from 175g of water to lower its temperature from 25.0 C to 15.0.C ? 5. How much heat in kJis needed to bring 1.0kg of water from 25.C to 99.C? M = 1.0kq C = 4, 14 AtE 99.C Atie 2506 9 = 310 kg 6. Calculate the amount of heat (in Joules) required to warm 400.0 g of water from 10 C to 35.C. 7. 17.556 kJ of heat are added to a 300.0 gram sample of water initially at 5 C. Calculate the final temperature of the water sample. 9 = 17. 586 KJ 17 5 56 = ( 300g) (4,184 7 ) ( Tf - S) M = 300 q C = 4, 189) 17 5 56 = (300-)( 4. 189 5/ ) (x-s) OTie SOC TF = (? ( 3005 ) / 4, 184 / . ) ( 300 g ) ( 4.1 89 JJgoc ) 175 56( 300 g ) (4 , 184 J) goc ~ - It - 18.99 = 202 8. What is the final temperature after 840 Joules is absorbed by 10.0g of water at 25.0 C? Hibum 22 0 get propane (Cold) in a bom 9. The temperature of a sample of water increases from 20C to 46.6 C as it absorbs 5650 calories of heat. What is the mass of the sample? 10. A food sample is burned in a calorimeter that contains 2000 g of water. The temperature increases from 22.0C to 44.3.C. How many Calories does the food sample contain? 11. A 3.6 gram food sample is burned completely in a calorimeter that contains 1000 g of water. The temperature of the water increases 23.65 .C. How many Calories does the food have per gram? 12. How many grams of water can be heated from 20.0 C to 75C using 12500.0 joules? 13. 35, 112 J of heat are added to a 500.0 gram sample of water initially at 7 .C. Calculate the final temperature of the water sample. Be careful with units!16. What is the final temperature after 840 Joules is absorbed by 10.0g of water at 25.0 .C? 17. The heat capacity of aluminum is 0.900 J/g .C. How much energy is needed to raise the temperature of a 8.50 x 102 g block of aluminum from 22.8C to 94.6C? 18. A piece of metal weighing 59.047 g was heated to 100.0 C and then put it into 100.0 g of water (initially at 23.7 .C). The metal and water were allowed to come to an equilibrium temperature, determined to be 27.8 .C. Assuming no heat lost to the environment, calculate the specific heat of the metal. (Hint: First calculate the heat absorbed by the water then use this value for "Q" to determine the specific heat of the metal in a second calculation)