A mixture of 1 kmol of gaseous methane and 2 kmol of oxygen initially at 298 K

Question:

A mixture of 1 kmol of gaseous methane and 2 kmol of oxygen initially at 298 K and 100 kPa burns completely in a closed, rigid container. Heat transfer occurs until the products are cooled to 1000 K. If the reactants and the products each form ideal gaseous mixtures, determine
(a) The amount of heat transfer (Q) and
(b) The final pressure (P2).