🎯 Knowledge Check
Chemistry — Acids, Bases And Salts
Frequently Asked Questions
Acids are substances that contain hydrogen and can donate hydrogen ions (H+) to other substances. They have a sour taste and turn blue litmus paper red.
Bases are bitter, slippery to touch, turn red litmus blue, and neutralize acids in chemical reactions.
Salts are ionic compounds formed when acids react with bases or metals, consisting of cations from the base and anions from the acid.
A neutralization reaction is when an acid reacts with a base to form a salt and water, cancelling out each other's properties.
pH < 7 means acidic, pH = 7 is neutral, and pH > 7 is basic.
Indicators are substances like litmus, phenolphthalein, and methyl orange that change color in acids and bases to identify their nature.
The formula is NaHCO3 and it is mainly used in baking and as an antacid.
Hydrochloric acid aids digestion in the stomach and maintains a low pH to help break down food.
Strong acids/bases completely ionize in water; weak acids/bases only partially ionize. Examples: HCl (strong acid), CH3COOH (weak acid).
Water of crystallization is the fixed number of water molecules chemically bonded with salts in their crystalline form.
Dilution involves adding water to an acid to lower its concentration, making it safer for use and handling.
Always add acid to water slowly with stirring to avoid splashes and excessive heat which can cause burns or break glass.
Ant stings inject formic acid causing pain; applying a base like baking soda neutralizes the acid and gives relief.
Bleaching powder (CaOCl2) is used for disinfecting water, bleaching laundry, and as an oxidising agent in chemical industries.
It is prepared by heating gypsum; used for making casts, sculptures, decorative designs, and filling wall cracks.