How many neutrons are there in `""_(38)^(88)Sr` ?

Options

A. 38
B. 50
C. 126
D. 88

Explanation

To find the number of neutrons in the isotope `""_(38)^(88)Sr`, we can follow these steps:

### Step 1: Understand the notation
The notation `""_(38)^(88)Sr` indicates that we are dealing with the element Strontium (Sr). The number at the bottom (38) is the atomic number (Z), which represents the number of protons in the nucleus. The number at the top (88) is the mass number (A), which is the total number of protons and neutrons in the nucleus.

### Step 2: Identify the atomic number and mass number
From the notation:
- Atomic number (Z) = 38 (number of protons)
- Mass number (A) = 88 (total number of protons and neutrons)

### Step 3: Use the formula for mass number
The mass number (A) can be expressed as:
\[ A = \text{Number of protons} + \text{Number of neutrons} \]
This can be rearranged to find the number of neutrons:
\[ \text{Number of neutrons} = A - \text{Number of protons} \]

### Step 4: Substitute the values
Now we can substitute the values we have:
- Number of protons = 38
- Mass number = 88

So,
\[ \text{Number of neutrons} = 88 - 38 \]

### Step 5: Calculate the number of neutrons
Perform the calculation:
\[ \text{Number of neutrons} = 88 - 38 = 50 \]

### Conclusion
Therefore, the number of neutrons in `""_(38)^(88)Sr` is **50**.

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