A-LevelChemistryGroup 2Feb/Mar 2025Paper 1 Q211 Mark
River water in an agricultural area contains NH4⁺, CO3²⁻, HCO3⁻, Cl⁻ and NO3⁻ ions. This water is treated by adding a calculated quantity of calcium hydroxide. What is precipitated from the river water when calcium hydroxide is added?
ACaCl2
BCaCO3
CCa(NO3)2
DNH4OH
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The correct answer is B. This question tests the candidate's understanding of group 2 within the Chemistrysyllabus. The examiner's mark scheme requires...
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