Three liquids, X, Y and Z, are examined, and the outcomes are given below. Tests: • add anhydrous cobalt(II) chloride: X changes from blue to pink, Y no change, Z changes from blue to pink • measure boiling point: X $100^\circ\text{C}$, Y $78^\circ\text{C}$, Z $103^\circ\text{C}$ What can be inferred about X, Y and Z from this evidence?
- AX is impure water; Y is not water; Z is pure water
- BX is impure water; Y is pure water; Z is impure water
- CX is pure water; Y is impure water; Z is not water
- DX is pure water; Y is not water; Z is impure water