One gram of coal on complete combustion liberates 18kJ of heat. Calculate the amount of coal required to liberate the same amount of heat that an electric heater of 2kW provides in one hour.

What is the amount of electricity required to deposit one mole of calcium form molten of CaCl_(2) ?

An electric bulb draws a current of 0.2A when the voltage is 220 volts then calculate the amount of electric charge flowing through it in one hour.​

Calculate the heat of combustion of coal when 10 g of coal on burning raises the temperature of 2 litres of water from 20^@C to 55^@C .

Write an expression for the amount of heat produced in a wire of resistance R and carrying a current I for time. An electric heater of resistance 10 ohm draws 15 A from the service mains for 2 hours. Calculate the heat developed in the heater?

Write an expression for the amount of heat produced in a wire of resistance R and carrying a current I for time. An electric heater of resistance 10 ohm draws 15 A from the service mains for 2 hours. Calculate the power of the heater.

An electric heater of resistance 8 Omega draws 15 A from service mains for 2 hour,Calculate the rate at which heat is developed in the heater.

In a refrigerator, one removes heat from a lower temperature and deposits to the surroundings at a higher temperature. In this process, mechanical work has to be done, which is provided by an electric motor. If the motor is of 1kW power, and heat is transferred from -3^@ C to 27^@C , find the heat taken out of the refrigerator per second assuming its efficiency is 50% of a perfect engine.

Gasoline has an enthalpy of combustion 24000 kJ/mol gallon. When gasoline burns in an automobile engine, approximately 30% of the energy released is used to produce mechanical work. The remainder is lost as heat transfer to the engine's cooling system. As a start on estimating how much heat transfer is required, calculate what mass of water could be heated from 25^(@)C to 75^(@)C by the combustion of 1.0 gallon of gasoline in an automobile? (Given : C(H_(2)O)=4.18 J//g^(@)C ) a) 34.45 kg b) 80.383 kg c) 22 kg d) 224 kg