Question

ter. If water
into 2 kg
b. Liquid ammonia is used in ice factory
for making ice from water. If w
at 20 °C is to be converted into 2
ice at 0 °C, how many grams
ammonia are to be evaporated)
(Given: The latent heat
vaporization of ammonia=341 call
Answer: 586.4
C. A thermally insulated pot has 150
ice at temperature 0 °C. How much
steam of 100 °C has to be mixed to it.
so that water of temperature 50 °C
will be obtained?
(Given : latent heat of
melting of ice = 80 cal/g.
latent heat of
vaporization of water = 540 cal/g.
specific heat of water = 1 cal/g °C)
Answer: 33 g
A calorimeter has mass 100 g and
specific heat 0.1 kcal/ kg °C. It
contains 250 gm of liquid at 30 °C
having specific heat of 0.4 kcal/kg
°C. If we drop a piece of ice of mass
10 g at 0 °C, What will be the
temperature of the mixture?
Answer: 20.8 °C​

Answer 1

Heat released in converting 2kg water at 20oC to 2kg ice at 0oC

=(2000×20×1)+(2000×80)

Mass of ammonia evaporated = m gram 

Heat used by ammonia  = m×341 

Heat loss = Heat gain

∴200000=m×341

m=586gram