BEFORE STARTING THE QUIZ READ THESE BOOSTUP POINTS OF ACID BASE AD SALT
Acids, Bases and Salts BOOSTUP POINTS
Acids
🢂 All acids generate hydrogen gas on reaction with metals.
🢂 All acids contain hydrogen ions (H+).
🢂 The sour taste of many fruits and vegetables, lemon for instance, is due to various types of acids present in them.
🢂 The digestive fluids of most animals and humans also contain acids.
🢂 Strong acids are corrosive and can burn your skin.
Bases
🢂 A base is a substance, which on dissolving in water yields hydroxyl ions (OH-) as the only negative ions.
🢂 A base may be an oxide or a hydroxide of a metal. If a base is soluble in water, it dissociates to form a metal ion and it is the only negative hydroxyl ion (OH-).
🢂 The bases which are soluble in water are called alkalis.
🢂 Bases are the chemical opposite of acids. They are bitter in taste and soapy to touch.
🢂 Sea water and detergents are some examples of substances that are basic.
🢂 Many bases are oxide or hydroxide compounds of metals.
🢂 Strong bases can also burn one's skin.
🢂 Acids and bases can be better distinguished with the help of indicators.
🢂 Indicators are substances that undergo a change of color with a change of acidic, neutral or basic medium.
🢂 Litmus, a purple dye extracted from the lichen plant, is commonly used as an indicator in laboratories.
🢂 Acids change the color of litmus solution to red, and bases change the color of litmus solution to blue
🢂 Soap is basic in nature and changes the color of the turmeric stain. It turns yellow again when the cloth is washed with plenty of water.
🢂 Metal + Acid ⇨ Salt + Hydrogen
🢂 Metal carbonate + Acid ⇨ Salt + Carbon dioxide + Water
🢂 Acid + Metal hydrogen carbonate ⇨ Salt + Carbon dioxide + Water
🢂 Mono-protic acid – Such type of acids produce one mole of H+ ions per mole of acid, e.g., HCl , HNO3, etc.
🢂 Di-protic acid – They can produce two moles of H+ ions per mole of acid, e.g., H2SO4.
🢂 Tri-protic acid – They produce three moles of H+ ions per mole of acid, e.g., H3PO4.
🢂 Poly-protic – They can produce more than three H+ ion per mole of acid
🢂 Strong acids: Which are completely (100%) ionized in aqueous solutions. Hence at equilibrium, the concentration of acid molecules is very less and concentration of hydrogen ion reaches to maximum, e.g., HCl, HNO3, HClO4.
🢂 Weak acids: They are only partially ionized in solution at equilibrium state. At equilibrium state, acid molecules are present and the concentration of hydrogen ion is less, e.g., HF, CH3COOH.
Strength of bases
🢂 Strong bases: They are completely ionized in water to produce hydroxide ions, e.g, sodium hydroxide: NaOH(s) ⇌⇌ Na+(aq) + OH-(aq)
🢂 Weak bases: Partially ionize and equilibrium lies mostly towards reactants side, e.g., ammonia in water: NH3(aq) + H2O(l) ⇌⇌ NH4+(aq) + OH-(aq)
🢂 On the basis of the number of hydroxide groups present in a base, they can be classified as monobasic (one OH-), dibasic (two OH-), tribasic (three OH-) bases and so on.
Acid & Base and Fire Extinguisher
🢂 Metal carbonate or metal hydrogen carbonate and acid are used in fire extinguisher to produce carbon dioxide gas.
🢂 Acid and metal carbonate or bicarbonate is kept in separate chambers in a fire extinguisher.
🢂 On emergency they are allowed to react with one another.
🢂 The carbon dioxide gas so produce is poured over fire.
🢂 As carbon dioxide does not support burning, it puts off the fire.
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