A mixture of 2 L of butene and 5 L of hydrogen was passed over a nickel catalyst.

A mixture of 2 L of butene and 5 L of hydrogen was passed over a nickel catalyst. the reaction went by 40%. determine the volumetric composition of the gas mixture after the reaction

Given:
V (C4H8) = 2 L
V (H2) = 5 L
R = 40%

Find:
φ (gases) -?

Solution:
1) C4H8 + H2 = (Ni) => C4H10;
2) V react. (C4H8) = R * V (C4H8) / 100% = 40% * 2/100% = 0.8 L;
3) V rest. (C4H8) = V (C4H8) – V re. (C4H8) = 2 – 0.8 = 1.2 L;
4) V react. (H2) = V react. (C4H8) = 0.8 L;
5) V rest. (H2) = V (H2) – V react. (H2) = 5 – 0.8 = 4.2 l;
6) V (C4H10) = V reag. (C4H8) = 0.8 L;
7) V mixture = V rest. (C4H8) + V rest. (H2) + V (C4H10) = 1.2 + 4.2 + 0.8 = 6.2 L;
8) φ (C4H8) = V rest. (C4H8) * 100% / V mixture = 1.2 * 100% / 6.2 = 19%;
9) φ (H2) = V rest. (H2) * 100% / V mixture = 4.2 * 100% / 6.2 = 68%;
10) φ (C4H10) = 100% – φ (C4H8) – φ (H2) = 100% – 19% – 68% = 13%.

Answer: The volume fraction of C4H8 is 19%; H2 – 68%; C4H10 – 13%.