2026 · Q26
Which one among the following pairs of compound and chemical formula is not correctly matched?
General KnowledgeChemistry
- ABleaching powder : CaOCl2
- BSoda ash : Na2CO3
- CBaking powder : NaHCl2
- DPlaster of Paris : 2CaSO4 . H2O
Explanation
The question asks for the pair that is not correctly matched. Bleaching powder is CaOCl2, soda ash is anhydrous sodium carbonate (Na2CO3), and plaster of Paris is CaSO4-half-H2O, written as 2CaSO4.H2O, all correctly matched. Baking powder, however, is sodium bicarbonate (NaHCO3) mixed with a weak acid; 'NaHCl2' is not even a valid chemical formula. Hence option C is the incorrectly matched pair.