Write the reaction equation: Ethane → butane → bromobutane → chlorobutane

Let us write down the reaction equations for the transformation chain:
Н3С – СН3 + Cl2 = H3C – CH2Cl + HCl – substitution reaction, chloroethane was obtained;
2С2Н5Cl + 2Na = C4H10 + 2NaCl – Wurtz reaction, butane was formed;
C4H10 + Br2 = C4H9Br + HBr – substitutions, bromobutane was isolated;
С4Н9Br + H2 = C4H10 + HBr – reduction, butane was obtained.
These reactions show the possibilities of obtaining various homologues of alkanes. The reaction products are of practical importance, for example, chloroethane, bromobutane are used as solvents.