Cambridge Past Paper Questions
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Phenol, C₆H₅OH, is a weak acid.
Benzene, C₆H₆, can be obtained from crude oil.
The proton NMR spectrum of compound E in the solvent CDCl₃ is shown. The molecular formula of compound E is C₉H₁₀O₂. [Figure X.X]
The table shows three pairs of monomers that are capable of polymerisation. Complete the table by identifying each type of polymerisation.
Aqueous potassium manganate(VII) can be used to determine the amount of iron present in a sample of iron wire by redox titration. Before potassium ...
A student uses the apparatus shown to calculate the relative molecular mass, Mr, of a gaseous alkane. The experiment took place at 298K and 101kPa....
Calcium hydroxide, Ca(OH)₂, is slightly soluble in water. Aqueous calcium hydroxide is also known as limewater. A student measures the concentratio...
Sodium thiosulfate reacts with excess dilute hydrochloric acid according to the following equation. Na₂S₂O₃(aq) + 2HCl(aq) → 2NaCl(aq) + S(s) + SO₂...
A student investigates the reaction between magnesium and hydrochloric acid to determine the order of reaction with respect to hydrochloric acid. T...
Compound X consists of 40.0% carbon, 6.7% hydrogen and 53.3% oxygen by mass. What is the empirical formula of compound X?
Technetium (Tc) is a second row transition element that does not occur naturally on Earth. One of its isotopes has 56 neutrons. What is the nucleon...
Which atom has more unpaired electrons than paired electrons in orbitals of principal quantum number 2?
Atom X is the central atom in a molecule. In this molecule, atom X has four pairs of valence electrons in its outer shell. The four pairs of valenc...
The strength of hydrogen bonding increases as the electronegativity of the element bonded to hydrogen increases. Some information for a range of hy...
The general gas equation can be used to calculate the value of the Mr of a gas. For a sample of a gas of mass m grams, which expression will give t...
The equation for the formation of ammonium chloride is shown. NH3(g) + HCl(g) ⇌ NH4Cl(s) ΔH = −314 kJ mol⁻¹ Which diagram shows the correctly label...
In a catalytic converter in the exhaust system of a car, carbon monoxide is oxidised to carbon dioxide, and nitrogen monoxide is reduced to nitroge...
NO and NO2 are both present in the lower atmosphere as pollutants. The reaction sequence shows the production of ozone from oxygen in the lower atm...
A mixture of two Period 3 oxides are added to water. A solution forms with a pH of just below 7. What could be the constituents of the mixture?
Which statement about the compounds of the Group 2 metals is correct?
A 0.005 mol sample of anhydrous calcium carbonate is completely thermally decomposed to give 100 cm³ of gas. In a separate experiment carried out u...
Redox reactions are common in the chemistry of Group 17 elements. Which statement is correct?
Silver chloride and silver iodide form equilibria when added to water. AgCl(s) ⇌ Ag⁺(aq) + Cl⁻(aq) K = K₁ AgI(s) ⇌ Ag⁺(aq) + I⁻(aq) K = K₂ Each equ...
X is the ion of a metal which burns with a red flame. Y is an ion that reacts with concentrated H2SO4 to produce H2S. What could be the formula of ...
Oxides of nitrogen are present in the environment due to natural and man-made sources. Which row is correct?
Magnesium hydroxide dissolves in aqueous ammonium chloride, but not in aqueous sodium chloride. Which statement explains this observation?
The formula of hydrocortisone acetate is shown. [Figure of hydrocortisone acetate structure] Which row is correct?
Bromomethane, CH3Br, decomposes in the stratosphere forming methyl free radicals and bromine free radicals. Which row correctly describes this deco...
Structural and stereoisomerism should be taken into account when answering this question. Y is a gaseous hydrocarbon which decolourises aqueous bro...
Butanoic acid can be made from 1-bromopropane in two stages. stage 1 CH3CH2CH2Br → CH3CH2CH2CN stage 2 CH3CH2CH2CN → CH3CH2CH2CO2H Which types of r...
Compound P is heated under reflux with an excess of acidified potassium dichromate(VI) to form compound Q. Compound Q has a lower boiling point tha...
Structural and stereoisomerism should be taken into account when answering this question. An organic compound, X, is dehydrated by heating with con...
Which compound produces a precipitate with 2,4-dinitrophenylhydrazine reagent and also with alkaline aqueous iodine?
Organic compound Z has an alcohol group and a carboxylic acid group. Compound Z reacts with magnesium carbonate to make a salt with a relative form...
The infra-red spectrum of Y is shown. [Figure showing an infra-red spectrum with transmittance % vs wavenumber /cm⁻¹] What could Y be?
The Boltzmann distribution diagram shows a fixed amount of a gas at two different temperatures, T₁ and T₂. [Figure of Boltzmann distribution diagra...
Four solutions, each of concentration 0.1 mol dm⁻³, were tested with a pH meter. The results are shown. solution | formula of acid or base | pH ---...
Which reactions are redox reactions? 1 Mg + 2HCl → MgCl2 + H2 2 2K2CrO4 + 2H⁺ → K2Cr2O7 + 2K⁺ + H2O 3 CuCO3 + 2HCl → CuCl2 + H2O + CO2
When the liquid N2F4 is heated, it decomposes into a single product, X. Which statements are correct? 1 N-F bonds are broken during this decomposit...
The following statements compare some properties of the oxides and chlorides of sodium and silicon. Which statements are correct? 1 The melting poi...
Which statements about ammonium chloride are correct? 1 It reacts with hot aqueous sodium hydroxide to produce an alkaline gas. 2 In solution, it r...
What is the same for a pair of optical isomers? 1 their empirical formula 2 their functional groups 3 their structural formula
Which of the molecular formulae represent at least one compound that can undergo addition polymerisation? 1 C4H8 2 C2H3Cl 3 C3H6O
Which of the reactions give products containing a chiral centre? 1 CH2(OH)COCO2H + an excess of HCN 2 CH2(OH)COCO2H + an excess of NaBH4 3 CH2(OH)C...
Ethyl butanoate is heated with a dilute aqueous solution of sodium hydroxide. Which substances are products of this reaction? 1 sodium butanoate 2 ...
Sulfides are compounds that contain sulfur but not oxygen.
The reaction scheme shows some reactions of calcium. [Figure 2.0]
Phosphorus is a reactive Period 3 element.
Compound B is a liquid with a fruity smell. [Figure 4.0] The reaction scheme shows how B can be made from ethanol, C2H5OH. [Figure 4.1]