To solve the problem of determining the ratio of \(\text{Cu}^{2+}\) to \(\text{Cu}^+\) ions in the sample of cuprous sulfide with the formula \(\text{Cu}_{1.92}\text{S}_{1.00}\), follow these steps:
### 1. **Understand the Composition:**
The formula \(\text{Cu}_{1.92}\text{S}_{1.00}\) indicates that the sample contains 1.92 copper (Cu) atoms for every 1 sulfur (S) atom.
### 2. **Determine the Charge Balance:**
In cuprous sulfide, the sulfur is in the \(\text{S}^{2-}\) oxidation state. To maintain electrical neutrality, the sum of the charges of copper ions must balance the charge of sulfur.
### 3. **Let \( x \) be the number of \(\text{Cu}^{2+}\) ions and \( y \) be the number of \(\text{Cu}^+\) ions.**
Since the total number of copper ions is given as 1.92, we have:
\[ x + y = 1.92 \]
The total charge must balance the charge of sulfur. Each \(\text{S}^{2-}\) ion contributes a charge of \(-2\), so for 1 sulfur atom:
\[ 2x + y = 2 \]
### 4. **Solve the System of Equations:**
We have two equations:
1. \( x + y = 1.92 \)
2. \( 2x + y = 2 \)
Subtract the first equation from the second to eliminate \( y \):
\[ (2x + y) - (x + y) = 2 - 1.92 \]
This simplifies to:
\[ x = 0.08 \]
Now substitute \( x = 0.08 \) into the first equation:
\[ 0.08 + y = 1.92 \]
Solve for \( y \):
\[ y = 1.92 - 0.08 = 1.84 \]
### 5. **Determine the Ratio:**
The ratio of \(\text{Cu}^{2+}\) to \(\text{Cu}^+\) is:
\[ \text{Ratio} = \frac{x}{y} = \frac{0.08}{1.84} \]
To simplify:
\[ \frac{0.08}{1.84} = \frac{8}{184} = \frac{1}{23} \]
### **Conclusion:**
The ratio of \(\text{Cu}^{2+}\) to \(\text{Cu}^+\) ions is \(1:23\), so the correct answer is:
**(b) 1:23**