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(a) Define the standard enthalpy of formation of a substance.
(b) Use the thermo chemical equations below to answer the questions that follow.
(i) Name two types of heat changes represented by ΔH3
(ii) Draw an energy level diagram for the reaction represented by equation 1.
(iii) Calculate the standard enthalpy of formation of ethane.
(iv) When a sample of ethane was burnt, the heat produced raised the temperature of 500g of water by 21.5 K.(specific heat capacity of water=4.2Jg-1K).
Calculate the:
I. Heat change for the reaction.
II. Mass of ethane that was burnt. (relative formula mass of ethane=30)