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Question
Write the formulae for the following and calculate the molecular mass for each one of them.
- Caustic potash
- Baking powder
- Limestone
- Caustic soda
- Ethanol
- Common salt
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Solution
| S.No. | Compound | Formula | Molecular Mass |
| a. |
Caustic potash |
KOH | 39 + 16 + 1 = 56u |
| b. | Baking powder | NaHCO3 | 23 + 1 + 12 + 3 × 16 = 84u |
| c. | Limestone | CaCO3 | 40 + 12 + 3 × 16 = 100u |
| d. | Caustic soda | NaOH | 23 + 16 + 1 = 40u |
| e. | Ethanol | C2H3OH | 2 × 12 + 5 × 1 + 16 + 1 = 46u |
| f. | Common salt | NaCl | 23 + 35.5 = 58.5u |
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