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(a) State two factors that should be considered when choosing fuel for cooking.
(b) The diagram below represents a set-up that was used to determine the molar heat of combustion of ethanol.
During the experiment, the data given below was recorded. Volume of water=#450cm^3# Initial temperature of water=#25^0C#
Final temperature of water=#46.5^0C#
Mass of ethanol+lamp before burning=125.5g
Mass of ethanol+lamp after burning=124.0g
Calculate the:
(i) Heat evolved during the experiment
(Density of water=#1gcm^-3#, specific heat capacity of water=#4.2Jg^-1K^-1#
(ii) Molar heat of combustion of ethanol (C=12.0, O=16.0, H=1.0)
(c ) Write the equation for the complete combustion of ethanol.
(d ) The value of the molar heat of combustion of ethanol obtained in (b) (ii) above is lower than the theoretical value. State two sources of error in the experiment.