A commercial sample of common salt has `45.5%` chlorine. What is the weight percentage of pure sodium chloride in the sample? 

Explanation

To find the weight percentage of pure sodium chloride (NaCl) in a commercial sample that contains 45.5% chlorine, we can follow these steps:

### Step 1: Calculate the molecular weight of sodium chloride (NaCl)
The molecular weight of NaCl is calculated by adding the atomic weights of sodium (Na) and chlorine (Cl).
- Atomic weight of Na = 23 g/mol
- Atomic weight of Cl = 35.5 g/mol

**Calculation:**
...