What is the chemical formula of (a) baking soda, and (b) washing soda?

Options

A. `Na_2CO_3 . 7H_2O`
B. `Na_2CO_3. 10H_2O`
C. `Na_2CO_3 . 3H_2O`
D. `Na_2CO_3`

Explanation

To find the chemical formulas for baking soda and washing soda, we can follow these steps:

### Step 1: Identify Baking Soda
Baking soda is commonly known as sodium bicarbonate.

### Step 2: Write the Chemical Formula for Baking Soda
The chemical formula for baking soda is:
\[ \text{NaHCO}_3 \]
This indicates that it contains one sodium (Na) atom, one hydrogen (H) atom, one carbon (C) atom, and three oxygen (O) atoms.

### Step 3: Identify Washing Soda
Washing soda is commonly known as sodium carbonate.

### Step 4: Write the Chemical Formula for Washing Soda
The chemical formula for washing soda is:
\[ \text{Na}_2\text{CO}_3 \cdot 10\text{H}_2\text{O} \]
This indicates that it contains two sodium (Na) atoms, one carbon (C) atom, three oxygen (O) atoms, and it is associated with ten water molecules (indicating it is a hydrate).

### Final Summary
- The chemical formula of baking soda is \( \text{NaHCO}_3 \).
- The chemical formula of washing soda is \( \text{Na}_2\text{CO}_3 \cdot 10\text{H}_2\text{O} \).

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