Same chapter2 marksDifficulty: Easy
What is a chemical formula? State what the formula H2SO4 tells you.
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Write the formulae of calcium carbonate, aluminium sulphate and ammonium chloride.
Original Khojo Papers practice question — not from a past board paper.
Answer
CaCO3, Al2(SO4)3 and NH4Cl
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The formula is found by crossing over the valencies: calcium and carbonate are both divalent, so the ratio is 1 : 1; aluminium is trivalent and sulphate divalent, so the ratio is 2 : 3.
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