By X-ray diffraction method, the unit cell edge length of sodium chloride is found to be 562.6 pm. The density of NaCl is observed to be `2.158 g cm^(-3)`.
(i) Predict the type of defect present in the crystal.
(ii) Calculate the percentage of `Na^(+)` and `Cl^(-)` ions missing.

Explanation

To solve the problem step by step, let's break it down into two parts as per the question.

### Part (i): Predict the type of defect present in the crystal.

1. **Understanding the Density Relation**:
The density (ρ) of a crystal can be calculated using the formula:
\[
\rho = \frac{Z \cdot M}{A^3 \cdot N_A}
...