Nitride ion in `Li_(3)N` is composed of

Options

A. 7 protons +7 electrons
B. 10 protons +7 electrons
C. 7 protons + 10 electrons
D. 10 protons + 10 electrons

Answer

To determine the composition of the nitride ion in Li₃N, we can follow these steps:

### Step 1: Identify the components of Li₃N
Li₃N consists of lithium (Li) and nitrogen (N). In this compound, lithium has a +1 charge, and there are three lithium ions.

### Step 2: Determine the charge of the nitride ion
Since there are three Li⁺ ions contributing a total charge of +3, the nitride ion (N³⁻) must have a charge of -3 to balance the overall charge of the compound to zero.

### Step 3: Find the atomic number of nitrogen
The atomic number of nitrogen (N) is 7, which means it has 7 protons.

### Step 4: Determine the number of electrons in neutral nitrogen
In a neutral nitrogen atom, the number of electrons is equal to the number of protons. Therefore, nitrogen has 7 electrons.

### Step 5: Calculate the number of electrons in the nitride ion
The nitride ion (N³⁻) has gained 3 additional electrons compared to neutral nitrogen. Thus, the total number of electrons in the nitride ion is:
\[ 7 \text{ (electrons in neutral N)} + 3 \text{ (additional electrons)} = 10 \text{ electrons} \]

### Step 6: Summarize the composition of the nitride ion
The nitride ion (N³⁻) consists of:
- 7 protons (from nitrogen)
- 10 electrons (7 from neutral nitrogen + 3 additional electrons)

### Final Answer
The nitride ion in Li₃N is composed of 7 protons and 10 electrons.

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