Determine the number of protons and neutrons in `""_(92)U^(238)` and `""_(90)Th^(234)`.

Answer

To determine the number of protons and neutrons in the isotopes \( _{92}^{238}U \) (Uranium) and \( _{90}^{234}Th \) (Thorium), we can follow these steps:

### Step 1: Identify the atomic number and mass number
- For \( _{92}^{238}U \):
- Atomic number (Z) = 92
- Mass number (A) = 238

- For \( _{90}^{234}Th \):
- Atomic number (Z) = 90
- Mass number (A) = 234

### Step 2: Determine the number of protons
The number of protons in an element is equal to its atomic number (Z).
- For Uranium \( _{92}^{238}U \):
- Number of protons = 92

- For Thorium \( _{90}^{234}Th \):
- Number of protons = 90

### Step 3: Calculate the number of neutrons
The number of neutrons can be calculated using the formula:
\[ \text{Number of neutrons} = \text{Mass number} - \text{Number of protons} \]

- For Uranium \( _{92}^{238}U \):
\[ \text{Number of neutrons} = 238 - 92 = 146 \]

- For Thorium \( _{90}^{234}Th \):
\[ \text{Number of neutrons} = 234 - 90 = 144 \]

### Final Results:
- For \( _{92}^{238}U \):
- Number of protons = 92
- Number of neutrons = 146

- For \( _{90}^{234}Th \):
- Number of protons = 90
- Number of neutrons = 144

### Summary:
- Uranium \( _{92}^{238}U \): 92 protons, 146 neutrons
- Thorium \( _{90}^{234}Th \): 90 protons, 144 neutrons