The valency of sulphur

The valency of sulfur (sulphur) can vary depending on the compounds it forms. Generally, sulfur can exhibit several oxidation states that correspond to its valency:

1. **-2**: In sulfide compounds (e.g., H₂S), sulfur has a valency of -2.
2. **+4**: In compounds like sulfur dioxide (SO₂), sulfur has a valency of +4.
3. **+6**: In compounds such as sulfuric acid (H₂SO₄) or sulfate ions (SO₄²⁻), sulfur exhibits a valency of +6.

Therefore, sulfur can have valencies of -2, +4, and +6 depending on the context of the chemical reactions and the compounds it forms.