Calculate the heat of combustion of coal, when 10 gm of coal, on burning raises the temperature of 2 kg of water from 20°C to 55°C

Calculate the entropy change when 50 gm water changes the temperature from 0^@C to 40^@C .

Calculate the amount nof heat required to change 5.0 kg of a ice to -20°C into steam at 100°C .

A brass boiler has a base area of 0.15 m2 and thickness 1.0 cm. It boils water at the rate of 6.0 kg/min when placed on a gas stove. Estimate the temperature of the part of the flame in contact with the boiler. Thermal conductivity of brass = 109 J s ^-1m^- 1K^-1 , Heat of vaporisation of water = 2256 xx 10^3 J kg^-1 .

Calculate the minimum amount of water at 15°C needed to cool 200g of mercury at 80°C to a temperature of 24°C (specific heat of mercury=0.033).

Calculate the amount of work done on 1gm-mole gas at 27^@C when volume increase twice isothermally.

Calculate the power of a motor in kilo-watt ,which is capable of rising 200 kg of water in five minutes from a ell 120 meter deep [ g=10ms^-2 ].

Calculate the depression in the freezing point of water when 10 g of CH_3CH_2CHClCOOH is added to 250 g of water. K_a = 1.4xx10^-3 , K_f = 1.86 K kg mol^-1 .

Calculate the rate of loss heat through a glass window of area 1000sq.cm. and thickness 4mm when the temperature inside is 37°C and outside is 5°C ( K for glass =0.0022)

Amount of heat required to convert 10 gm of ice to water at 20°C is

Calculate the amount of heat produced when 2kg substance pulled in a floor with a velocity 2m/s in 5 sec.