Acids & Bases
Chemistry · अम्ल और क्षार · 20 facts
Acid: H+ in water; sour; blue litmus red; pH<7
Base: OH- in water; bitter, soapy; red litmus blue; pH>7
pH: 0-14; 7=neutral(water); <7 acidic; >7 basic
Strong acids: HCl, H2SO4, HNO3 (fully ionize)
Weak acids: CH3COOH(vinegar), H2CO3, citric (partial)
Strong bases: NaOH(caustic soda), KOH, Ca(OH)2(slaked lime)
Neutralization: Acid+Base->Salt+Water; exothermic
Stomach HCl aids digestion; antacid Mg(OH)2 neutralizes excess
Acid rain: pH<5.6; SO2+NOx; damages marble buildings, crops
Indicators: Litmus, Phenolphthalein(colorless/pink), Methyl orange(red/yellow)
Turmeric turns red/brown in base — natural indicator
Bee sting acidic: apply baking soda; Wasp basic: apply vinegar
Blood pH: 7.35-7.45(slightly alkaline); gastric juice pH~2
Acid+Metal->Salt+H2; Acid+Carbonate->Salt+H2O+CO2
Baking soda NaHCO3: cooking, antacid, fire extinguisher
Washing soda Na2CO3.10H2O: cleaning, glass making
Plaster of Paris CaSO4.0.5H2O: broken bone casts, decoration
Bleaching powder Ca(OCl)Cl: water purification, textile bleaching
Tooth enamel corrodes below pH 5.5; acidic food causes decay
Universal indicator: different colours at different pH values