In copper(II) phosphate, which one of the following statements is false?
a) The oxidation number of oxygen is -2 .
b) The oxidation number of the phosphate ion is -3 .
c) The oxidation number of copper is +2 .
d) The oxidation number of phosphorus is +5 .
The Correct Answer and Explanation is :
The false statement is:
b) The oxidation number of the phosphate ion is -3.
Explanation:
Copper(II) phosphate is a compound with the chemical formula Cu₃(PO₄)₂. To determine which statement is false, let’s analyze each oxidation state.
- Oxidation Number of Oxygen (-2) (Statement a – True):
- Oxygen in most compounds (except peroxides and superoxides) has an oxidation number of -2.
- In phosphate (PO₄³⁻), each of the four oxygens has an oxidation state of -2.
- Oxidation Number of the Phosphate Ion (Statement b – False):
- The phosphate ion (PO₄³⁻) itself has an overall charge of -3, but the statement refers to its oxidation number as a whole.
- The oxidation number of an ion represents the charge of the central atom, not the entire ion.
- The correct term should be the charge of the phosphate ion is -3, rather than its oxidation number.
- Oxidation Number of Copper (+2) (Statement c – True):
- Copper(II) refers to the +2 oxidation state of Cu.
- The formula Cu₃(PO₄)₂ means that three Cu²⁺ ions balance two PO₄³⁻ ions.
- Oxidation Number of Phosphorus (+5) (Statement d – True):
- In PO₄³⁻, let the oxidation number of phosphorus be x:
[
x + (4 \times -2) = -3
]
[
x – 8 = -3
]
[
x = +5
] - This confirms that phosphorus has an oxidation number of +5.
Since statement (b) incorrectly describes the oxidation number of the phosphate ion, it is the false statement. Now, I will generate an image representing copper(II) phosphate.
Here is a 3D molecular model of Copper(II) Phosphate (Cu₃(PO₄)₂), visually representing the ionic interactions between Cu²⁺ ions and phosphate groups. Let me know if you need any modifications or further clarifications!