$1$ mole of $C{H}_4(1$ bar, $($:$50C\}$ is mixed with $1$ mole of $O_2(\frac{1}{b}ar,50C)$ to form a mixture at $2$ bar and $50C.$ The Gibbs Energy change is $q,$ Explain your answer.

a$.$ Positive

b$.$ Negative

c$.$ Zero