The number of `pi` bonds in naphthalene is y, number of `sigma` bonds in z and number of carbon atoms is x. calculate the value of `(y+z)/(x)` ?

Answer

To solve the problem, we need to determine the values of \(y\), \(z\), and \(x\) for naphthalene and then calculate \((y + z) / x\).

### Step 1: Determine the number of carbon atoms (x) in naphthalene.
Naphthalene has a fused ring structure consisting of two benzene rings. Each benzene ring contains 6 carbon atoms, but since they share 2 carbon atoms at the fusion point, the total number of carbon atoms is:

\[ x = 10 \]

### Step 2: Determine the number of pi bonds (y) in naphthalene.
In naphthalene, there are 5 double bonds. Each double bond consists of one pi bond. Therefore, the total number of pi bonds is:

\[ y = 5 \]

### Step 3: Determine the number of sigma bonds (z) in naphthalene.
To count the sigma bonds, we consider both the carbon-carbon and carbon-hydrogen bonds.

- Each carbon atom in naphthalene is bonded to either 1 or 2 hydrogen atoms (depending on its position in the structure).
- The 10 carbon atoms form 9 carbon-carbon sigma bonds (since there are 10 carbon atoms, there are 9 bonds connecting them).
- Additionally, there are 8 hydrogen atoms bonded to the carbon atoms.

Thus, the total number of sigma bonds is:

\[ z = \text{(C-C bonds)} + \text{(C-H bonds)} = 9 + 10 = 19 \]

### Step 4: Calculate \((y + z) / x\).
Now that we have \(y\), \(z\), and \(x\):

\[ y = 5, \quad z = 19, \quad x = 10 \]

Now we can calculate:

\[ \frac{y + z}{x} = \frac{5 + 19}{10} = \frac{24}{10} = 2.4 \]

### Final Answer:
The value of \((y + z) / x\) is \(2.4\).