Answer
See the answer below.
Work Step by Step
a) From the diagram it's methane (955.1 kJ vs 676.1 kJ)
b)
Methane:
$-955.1\ kJ/mol\times16.04\ g/mol=-59.55\ kJ/g$
Methanol:
$-676.1\ kJ/mol\times 32.04\ g/mol=-21.10\ kJ/g$
It's methane again.
c) From the diagram:
$-955.1--676.1=-279.0\ kJ/mol$
d) From the diagram, cancelling the excess oxygen:
$CH_4(g)+1/2\ O_2(g)\rightarrow CH_3OH(l)$
