Which compound is used as an antacid?
- NaCl
- NaHCO₃
- HCl
- H₂SO₄
Answer: NaHCO₃
Sodium bicarbonate (baking soda) neutralizes excess stomach acid (HCl), relieving acidity. Modern antacids use Mg(OH)₂, Al(OH)₃. Common application of acid-base chemistry. [[NCERT Chemistry Class 10]]