Question

When Cl₂ reacts with hot and conc. NaOH, the oxidation number of chlorine changes from ____________.

Options

• zero to +1 and zero to +5

• 0 to −1 and 0 to +5

• zero to −1 and zero to +3

• 0 to +1 and 0 to −3

Answer 1

When Cl₂ reacts with hot and conc. NaOH, the oxidation number of chlorine changes from 0 to −1 and 0 to +5.

Explanation:

C_l2 has oxidation number 0, in Cl (−1) and in ClO₃ (+5).

\[\ce{3Cl2 + 6NaOH ({hot and conc.}) -> 5NaCl + NaClO3 + 3H2O}\]