AS & A Level Chemistry (9701) — May–June 2025, Paper 41
10 questions · every question answerable online with instant point-by-point AI marking against the official mark scheme.
Start with Question 1 →Both calcium carbonate, CaCO3, and barium carbonate, BaCO3, decompose when heated to form the metal oxide and a gas. Write an equation for the thermal decomposition of CaCO3.
Answer this question and get it marked →Three experiments are carried out to investigate the reaction of nitrogen oxide, NO, with chlorine. 2NO + Cl2 → 2NOCl The rate equation for this reaction is: rate = k[NO]2[Cl2]…
Answer this question and get it marked →Chromium(III) hydroxide, Cr(OH)3, is only slightly soluble in water. The value of the solubility product, Ksp, of Cr(OH)3 is 1.0 × 10−33 at 298 K. (i) Complete the expression for…
Answer this question and get it marked →Table 4.1 gives the enthalpy changes of hydration, ΔHhyd, of three ions, F−, K+ and Ca2+. Table 4.1: ion ΔHhyd / kJ mol−1 F− −506 K+ −322 Ca2+ −1650 (i) Define enthalpy change of…
Answer this question and get it marked →Copper is a transition element. (i) Complete the electronic configurations of a Cu+ ion and a Cu2+ ion. Cu+ ion: [Ar] ... Cu2+ ion: [Ar] ... (ii) Explain why transition elements…
Answer this question and get it marked →Iron forms complex ions with the monodentate ligand, CN−. Complex ion A contains one Fe3+ ion and six CN− ligands. Complex ion B contains one Fe2+ ion and six CN− ligands. (i)…
Answer this question and get it marked →A hydrocarbon is known to be either compound D or compound E. D is 1,2-diethylbenzene (a benzene ring with two CH2CH3 groups at positions 1 and 2). E is 1,3-diethylbenzene (a…
Answer this question and get it marked →Bromine reacts with methylbenzene in the dark in the presence of a suitable catalyst to form HBr and compound L, C7H7Br. L is one of three isomers that can form in this reaction.…
Answer this question and get it marked →Phenylamine, C6H5NH2, and propylamine, CH3CH2CH2NH2, can be produced by different reduction reactions. (i) Identify an organic compound that can be converted into C6H5NH2 by a…
Answer this question and get it marked →Propanoic acid, methanoic acid and ethanedioic acid are all weak acids. Draw the displayed formula of ethanedioic acid.
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