The newest 18 of 18 written questions. Open one to see it on the real paper.
Aqueous iron( III ) sulfate contains iron( III ) ions, Fe 3+ , and sulfate ions, SO 42− . Deduce the formula of iron( III ) sulfate.
See it on the paper →State the total number of atoms shown in this formula.
See it on the paper →What is the formula of ammonium phosphate?
See it on the paper →Construct the word equation for this reaction. + +
See it on the paper →has the formula PbBr 2 .
See it on the paper →is a salt from which ammonia can be displaced.
See it on the paper →State the number of different elements shown in this formula.
See it on the paper →State the total number of atoms shown in this formula.
See it on the paper →The formula of phosphorus oxide is P 4 O 10 . State the number of atoms of phosphorus and of oxygen contained in one molecule of phosphorus oxide. phosphorus oxygen
This proved more challenging to candidates than 8(a)(i). 50 was a common incorrect answer, a result of adding up the masses of the atoms but many other figures were given.
— Examiner report, May/June 2025, 0654/33 Q8(a)(ii) (Cambridge)
Few candidates correctly identified both the reactants and the products in the reaction. A number of candidates suggested water as either a reactant or a product.
— Examiner report, October/November 2023, 0654/33 Q8(a)(i) (Cambridge)
Ammonium nitrate was less well known. Many candidates suggested sodium chloride, perhaps in an attempt to name a salt.
— Examiner report, May/June 2023, 0654/33 Q2(a)(ii) (Cambridge)
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Potassium oxide is also an ionic compound. Potassium ions, K + , combine with oxide ions, O 2– , to form potassium oxide. Determine the formula of potassium oxide.
See it on the paper →State the name of the salt made.
See it on the paper →The formula of copper( II ) sulfate is CuSO 4 . State the number of different elements and the total number of atoms shown in this formula. number of elements number of atoms
See it on the paper →Magnesium chloride is also made in the reaction between magnesium and dilute hydrochloric acid. Magnesium chloride contains the ions Mg 2+ and Cl – . Determine the formula of magnesium chloride.
See it on the paper →State the total number of atoms shown in this formula.
See it on the paper →Which row shows the total number of different elements and the total number of atoms in the three structures?
See it on the paper →Which row shows the total number of different elements and the total number of atoms in the three structures?
See it on the paper →Which row shows the total number of different elements and the total number of atoms in the three structures?
See it on the paper →Solid aluminium chloride is another ionic compound. Aluminium chloride contains aluminium ions, Al 3+ , and chloride ions, Cl – . Determine the formula of aluminium chloride.
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