To neutralize 500 ml of hydrochloric acid (HCl), you need approximately 2 grams of baking soda (sodium bicarbonate, NaHCO3).
Here’s the explanation: Hydrochloric acid is a strong acid, and to neutralize it, we use a base like baking soda. The reaction that occurs is:
NaHCO₃ + HCl → NaCl + CO₂ + H₂O
This indicates that one mole of sodium bicarbonate reacts with one mole of hydrochloric acid.
The concentration of hydrochloric acid is essential in determining the exact amount needed. For a typical dilute HCl solution (approximately 1 mole per liter), 500 ml contains 0.5 moles of HCl. Thus, you’d also need 0.5 moles of NaHCO3 to fully neutralize it. Since one mole of baking soda weighs about 84 grams, for 0.5 moles, you would need:
(0.5 moles) × (84 g/mole) = 42 g of baking soda
If the hydrochloric acid solution you have is less concentrated, adjust accordingly. Always make sure to measure carefully and add the baking soda slowly to avoid excessive bubbling and splattering!