Question

Temperature and Specific Heat sub Rice Chest 3,205 g no ni 103.20 C. Energy and Nutrition 1. Type of food sample 2. Mass of aluminum can 3. Mass of aluminum can and water 4. Mass of food 5. Initial temperature of water 6. Final temperature of water 7. Mass of ash or food remaining Calculations 10.520g 22.00€ 23.5 o 2,2 coe 8. Mass of water (3 - 2) 9. Temperature change for water (6-5) 10. Heat gained by water (Show calculations.) too 11. Heat (cal) given off by burning of food sample 12. Heat (kcal) given off by burning of food sample 13. Mass of food undergoing combustion (4-7) 14. Energy value (kcal/g) of food sample (Show calculations.)

Answer 1

10) Heat gained by water = q = mc *(T2 - T1) , where C is the specific heat of water, T2-T1 is the change in temperature, m is the mass of water

q = 100 g * 4.18 J/goC * 1.5 oC = 627 J = 150 calories

11) The heat that was gained by water = Energy obtained by burning off the food =150 cal

12) Energy obtained in kilocalories=  150 /1000 = 0.15 kCal

13) Mass of food undergoing combustion = (10.52 -7.203 ) g =3.32 g

14) Energy content = Energy burned / mass of food burned = 0.15 kCal / 3.32 g = 0.045 kCal/g = 45 cal/g