Напишите уравнения реакций CH4 → X1 → C2H4 → X2 → C4H10 → X3

1) 2 CH4 →  HC ≡ CH + 3H2↑
2) HC ≡ CH + H2→CH2=CH2
3) CH2=CH2 + HBr → CH3CH2Br
4) 2CH3CH2Br + 2Na →CH3CH2 CH2CH3 + 2NaBr
5) CH3CH2 CH2CH3→CH3-CH-CH3
                                               CH3