Can anyone help me with this? Structural formula of:

1)2, 2 diethyl butane
2)2, 3 dimethyl pentane

The solid xy decomposes into gaseous x and y: xy(s) m x(g) + y(g) kp = 4.1 (at 0 °c) if the reaction is carried out in a 22.4 l container, which initial amounts of x and y will result in the formation of solid xy?