The number of electrons in deuterium is

Options

A. `2`
B. `3`
C. `1`
D. `0`

Explanation

To determine the number of electrons in deuterium, we can follow these steps:

### Step 1: Understand what deuterium is
Deuterium is an isotope of hydrogen. Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons.

**Hint:** Remember that isotopes have the same atomic number but different mass numbers.

### Step 2: Identify the atomic structure of deuterium
Deuterium has:
- 1 proton
- 1 neutron
- 1 electron

The presence of one proton indicates that it is hydrogen, and since it is deuterium, it has one neutron in addition to the proton.

**Hint:** The number of protons in an atom determines its element.

### Step 3: Determine the number of electrons
In a neutral atom, the number of electrons is equal to the number of protons. Since deuterium has 1 proton, it will also have 1 electron.

**Hint:** In a neutral atom, protons and electrons are balanced.

### Conclusion
Therefore, the number of electrons in deuterium is 1.

**Final Answer:** The number of electrons in deuterium is 1.

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