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`.

Calculate the mass 10^20 atoms of C.

Calculate the number of kJ of heat neccesary to raise the temperature of 60.0g of aluminum from 35^(@) C to 55^(@)C . Molar heat capacity of Al is 24 J mol^(-1) k^(-1) .

In a zero-order reaction for every 10^@ rise of temperature, the rate is doubled. If the temperature is increased from 10^@ C to 100^@C , the rate of the reaction will become

What type of reaction is combustion of coal and formation of water from H_2 and O_2 ?

What is the activation energy for a reaction if its rate double when the temperature raised from 20^@C to 35^@C ? (R=8.314J//mol//K)

Calculate the kinetic energy of 0.2 g of H_2 at 27^@C .

What happens when coal is heated or burn in air?

Assuming a domestic refrigerator a reversible engine working between melting point of ice and the room temperature of 17^@C .Calculate the enrgy in joule that m ust be suppled to freeze 2kg of water .Given that temperature of water = 0^@C nd L=80 cal//g .

The rate constant for the first order reactior becomes three times when the temperatur is raised from 20^@ C to 50^@ C. Calculate the energy of activation for the reaction.