1.1. Alkanes can be used as fuels in internal combustion engines. When sufficient oxygen is present, they undergo complete combustion reactions.

Write an equation for the complete combustion of butane.

1.2. Define the term standard enthalpy of combustion, Δ_cH^ϴ. 

1.3. Table 1 below contains bond enthalpy data for the reaction shown in part (a). 

Table 1

i) Using the data in Table 1 and the equation in part (a), calculate the enthalpy change of combustion of butane.

ii) State whether this reaction is endothermic or exothermic. Explain your answer.

1.4. The values given in Table 1 in part (c) are mean bond enthalpies.

State the meaning of the term mean bond enthalpies.