Which of the following compounds have the oxidation number of the metals as +1?

Options

A. `CuSCN`
B. `K_(3)[Cu(CN)_(4)]`
C. `[Fe(H_(2)O)_(5)NO]SO_(4)`
D. `Cu_(2)O`

Answer

To determine which of the given compounds have the oxidation number of the metals as +1, we will analyze each compound step by step.

### Step 1: Analyze the first compound (C-U-S-C-N)
- The compound is C-U-S-C-N, where C-U is copper and S-C-N is the thiocyanate ion.
- Let the oxidation state of copper (Cu) be \( X \).
- The thiocyanate ion (SCN) has a charge of -1.
- The equation for the oxidation state can be set up as:
\[ X + (-1) = 0 \]
- Solving for \( X \):
\[ X = +1 \]
- Therefore, in C-U-S-C-N, the oxidation number of copper is +1.

### Step 2: Analyze the second compound (K-3-C-U-C-N-4)
- The compound is K₃Cu(CN)₄.
- Potassium (K) has an oxidation state of +1, and there are 3 potassium ions, contributing a total of +3.
- Let the oxidation state of copper (Cu) be \( X \).
- The cyanide ion (CN) has a charge of -1, and there are 4 cyanide ions, contributing a total of -4.
- The equation for the oxidation state can be set up as:
\[ 3 + X - 4 = 0 \]
- Solving for \( X \):
\[ X - 1 = 0 \implies X = +1 \]
- Therefore, in K₃Cu(CN)₄, the oxidation number of copper is +1.

### Step 3: Analyze the third compound (F-E-H-2-O-5-N-O-S-O-4)
- The compound is Fe(H₂O)₅NO(SO₄).
- Let the oxidation state of iron (Fe) be \( X \).
- Water (H₂O) has no charge, NO has a charge of -1, and sulfate (SO₄) has a charge of -2.
- The equation for the oxidation state can be set up as:
\[ X + 0 + (-1) + (-2) = 0 \]
- Solving for \( X \):
\[ X - 3 = 0 \implies X = +3 \]
- Therefore, in Fe(H₂O)₅NO(SO₄), the oxidation number of iron is +3.

### Step 4: Analyze the fourth compound (C-U-2-O)
- The compound is Cu₂O.
- Let the oxidation state of copper (Cu) be \( X \).
- There are 2 copper atoms, and oxygen (O) has a charge of -2.
- The equation for the oxidation state can be set up as:
\[ 2X + (-2) = 0 \]
- Solving for \( X \):
\[ 2X = +2 \implies X = +1 \]
- Therefore, in Cu₂O, the oxidation number of copper is +1.

### Conclusion:
The compounds that have the oxidation number of the metals as +1 are:
1. C-U-S-C-N (Cu)
2. K-3-C-U-C-N-4 (Cu)
3. C-U-2-O (Cu)