RACE IIT & MEDICAL ACADEMY (FOUNDATION COURSE FOR IX & X CLASSES ) 1. Find the amount of heat required by 1 g of ice at 0°C for complete conversion into steam at 100°C. 2. 100 grams of water requires the same amount of heat as 1000 grams of metal for the same rise of

temperature. What is the specific heat of metal ? 3. 200 grams of mercury requires 30 cals for 5°C rise of temperature. Find the specific heat of mercury. 4. The water equivalent of a calorimeter is 6 grams. Its mass is 60 grams What is specific heat of

calorimeter ? 5. 100 grams of hot water at 100°C is pored into a calorimeter of mass 100 grams at 20°C. Find the

resultant temperature of the calorimeter. (s = 0.01 cal g–1 °C–1) 6. Two lead spheres at the same temperature have radii in the ratio of 1:2. Find the ratio of their heat

capacities ? 7. If some water at 100°C is mixed with twice the quantity of water at 70°C, find the equilibrium

temperature. 8. When steam at 100°C is passed over a large block of ice, 64 grams of ice melts. What is the amount

of steam condenses ? 9. Two bodies have their masses in the ratio 1:2 and the specific heats are in the ratio of 2:1. What is the

ratio of their thermal capacities ? 10. There are two lead spheres at the same temperature, the ratio of their radii being 1:2. What is the ratio

of their heat capacities ? 11. The densities of two substances are in the ratio of 5:6 and their specific heats are in the ratio 3:5. What

is the ratio of their thermal capacities per unit volume ? 12. If the thermal capacity of a cube of edge 1 cm is 0.8 cal/°C, find the thermal capacity of a cube of edge

2 cm made of the same material. 13. If the specific heat of aluminium is 0.25 cal/g/°C, find the water equivalent of an aluminium vessel of

mass 0.5 kg. 14. If some water at 100°C is mixed with twice the quantity of water at 70°C, find the equilibrium

temperature. 15. What will be the final temperature if 50 g of water at 0°C is added to 250 g of water at 90°C? 16. 34 g of water at 30°C is poured into a calorimeter whose temperature is 15°C. If the final temperature

of the two is 20°C, calculate the water equivalent of the calorimeter. 17. A liquid of specific heat 0.5 cal/g/°C at 60°C is mixed with another liquid of specific heat

0.3 cal/g/°C at 20°C. If the resultant temperature is 30°C, in what proportion by masses are the liquids mixed ?

18. How many calories of heat are required to convert 5 grams of ice into water at 40°C ? 19. A metal ball of mass 100 grams is heated to 100°C and then dropped into a block of ice which is at

0°C. It is found that 12.5 grams of ice has been converted into water. What is the specific heat of the metal ?

20. An ice cube of mass 40 grams is taken from a refrigerator where its temperature is 10°C and dropped into a glass of water at 0°C. If no heat is gained or lost from outside, how much water will freeze on to the ice cube ?