Isotopes have identical atomic numbers (number of protons) but different mass numbers due to different numbers of neutrons. They have similar chemical properties but different physical properties like mass and density. Example: ¹²C and ¹⁴C, both have 6 protons.
Explanation:
Photochemical smog is formed in sunny, dry cities due to the reaction of sunlight with nitrogen oxides and volatile organic compounds (from vehicle exhaust). This produces secondary pollutants like ozone (O₃), peroxyacetyl nitrate (PAN), and aldehydes, which make up the harmful smog.
Explanation:
J.J. Thomson discovered the electron and proposed the 'plum pudding' model (positive sphere with embedded electrons). Rutherford proposed the nuclear model after the gold foil experiment. Bohr gave quantized orbits. Dalton gave the solid sphere model.
Explanation:
Ethylene glycol (1,2-ethanediol) is the main component of antifreeze, lowering the freezing point of water. Methanol is toxic, ethanol can be used but evaporates, glycerol is viscous. Ethylene glycol is poisonous if ingested. Propylene glycol is a safer alternative.
No comments yet. Be the first to start the discussion!