Cambridge Past Paper Questions
Browse 23,045questions from 25 years of O-Level & A-Level exams. Click any question to practice.
Separate samples of magnesium and calcium are added to an excess of dilute sulfuric acid. The observations are summarised in the table. metal: magn...
Dolomite is a double carbonate, CaMg(CO₃)₂, and can be used instead of calcium carbonate for treating acidic soils. The three statements all refer ...
This question is about two salts, NaI and NaCl. The two solid salts are separately added to warm concentrated H₂SO₄ and the results noted. Aqueous ...
The diagram shows the process of adding calcium nitrate and strontium nitrate to separate boiling tubes and heating them. Identical conditions are ...
The equations for three reactions involving chlorine or its compounds are listed. 1 2KClO₃ → 2KCl + 3O₂ 2 4KClO₃ → 3KClO₄ + KCl 3 6KOH + 3Cl₂ → 3H₂...
Nitrogen monoxide, NO, is a primary pollutant produced by petrol engines and is found in their exhaust gases. Which reaction occurs in a catalytic ...
The diagram shows the structure of the naturally occurring molecule cholesterol. [Figure showing the skeletal structure of cholesterol] Student X s...
The drug cortisone has the formula shown. [Figure showing the skeletal structure of cortisone with three chiral centers marked by asterisks] In add...
But-2-ene reacts with cold dilute acidified KMnO₄ to give product X. But-2-ene reacts with hot concentrated acidified KMnO₄ to give product Y. Whic...
A sequence of reactions takes place. The major product is compound Z. [Figure showing reaction scheme: propanoic acid --(LiAlH₄)--> compound X --(c...
Which statement is correct?
In the hydrolysis of bromoethane by aqueous NaOH, what is the nature of the attacking group and of the leaving group?
X is an organic compound containing the elements carbon, hydrogen and oxygen only. The table shows the observations made from three chemical tests ...
How many moles of oxygen gas are needed for the complete combustion of 1 mol of (CH₃)₃COH?
In which pair will each compound give a different visible result with alkaline I₂(aq)?
Which reagent gives a positive result with propanone?
Esters can be hydrolysed with an aqueous alkali or an aqueous acid to form two products. The table compares the two methods. Which row is correct?
Structural isomerism only should be considered when answering this question. How many compounds with molecular formula C₅H₁₁Br are primary halogeno...
Compound Z is formed by the reaction scheme shown. [Figure showing reaction scheme: CH₃CH₂Br --(warm with KCN in ethanol)--> compound X --(reflux w...
Hydroxyethanal, HOCH₂CHO, is heated under reflux with an excess of acidified K₂Cr₂O₇ until no further oxidation takes place. What is the skeletal f...
The formula shows the repeat unit of an addition polymer. -CH(CH₃)CH(CH₂CH₃)- What is the correct name of the monomer from which this polymer is made?
The infrared spectrum of a compound is shown. [Figure showing an infrared spectrum graph] [Table of characteristic infrared absorption ranges] Whic...
Bismuth is an element in Group 15 of the Periodic Table.
Chlorine, Cl2, reacts with many elements and compounds to form chlorides. Table 2.1 shows information about some chlorides of Period 3 elements. Ta...
Nitrogen, N2, is generally an unreactive molecule but it does react under certain conditions.
Compound S is used in food flavourings. A possible synthesis of S is shown in Fig. 4.1. P HBr reaction 1 Q KCN in ethanol reaction 2 R CN H+(aq) re...
In this experiment you will determine the enthalpy change, ΔH, for the reaction between aqueous copper(II) sulfate and magnesium. CuSO4(aq) + Mg(s)...
Potassium iodide, KI, is used as a reagent in both inorganic and organic chemistry.
Water is an amphoteric compound that also acts as a good solvent of polar and ionic compounds.
Iron is a transition metal in Group 8 of the Periodic Table.
Ruthenium and osmium are transition metals below iron in Group 8 of the Periodic Table.
Compound Q can be synthesised from chlorobenzene in seven steps, using the route shown in Fig. 5.1. [Figure 5.1, showing a seven-step reaction sche...
Amino acids are molecules that contain –NH2 and —COOH functional groups. Glycine, H2NCH2COOH, is the simplest stable amino acid.
Sea water contains about 20gdm-³ of chloride ions, Cl-(aq). The exact concentration of Cl-(aq) in sea water can be determined by titration with aqu...
A student wants to investigate the rate of the hydrolysis of methyl methanoate, HCOOCH3. HCOOCH3 + H2O ⇌ HCOOH + CH3OH The reaction is catalysed by...
A Boltzmann distribution for a sample of a reacting gas at a constant temperature is shown. The activation energy, EA, for the reaction is marked. ...
Crystals of copper(II) nitrate are prepared by adding an excess of malachite to nitric acid. The formula of malachite is Cu(OH)2•CuCO3. (Mr = 221.0...
X and Y are elements from the same group of the Periodic Table. The 5th to 9th ionisation energies for X and Y are shown. ionisation energy/kJmol⁻¹...
An ion with a charge of 2- contains 10 electrons and 14 neutrons. What is its nucleon number?
The structure of the hormone histamine is shown. Which row contains the bond angles x, y and z in histamine in the correct order from the smallest ...
When an organic acid reacts with an alcohol, a reversible reaction takes place producing an ester and water. 0.40 mol of an organic acid and 0.30 m...
Information about two substances is given. substance electrical conductivity effect of adding to water melting point...
An excess of zinc reacts with x cm³ of 2.00 mol dm⁻³ hydrochloric acid. The gas produced is dried and collected. The gas occupies 1.534 dm³ at 1010...
An aqueous solution of hydrogen peroxide is placed in a flask and decomposes, as shown. 2H2O2(aq) → 2H2O(l) + O2(g) The total volume of oxygen gas ...
Methanol is manufactured by reacting carbon dioxide and hydrogen together. CO2(g) + 3H2(g) ⇌ CH3OH(g) + H2O(g) ΔH = −49 kJ mol⁻¹ What increases the...
The equation for a reaction of KClO3 is shown. 4KClO3 → KCl + 3KClO4 Which row is correct? disproportionation oxidation number...
A student mixes 25.0 cm³ of 0.100 mol dm⁻³ sodium hydroxide solution with 25.0 cm³ of 0.100 mol dm⁻³ hydrochloric acid and the student records a te...
Carbon monoxide and methanol can react together to form ethanoic acid. CO(g) + CH3OH(l) →ΔH CH3CO2H(l) Standard enthalpy changes of combustion are ...
Copper reacts with nitric acid under certain conditions. The products are copper(II) nitrate, water and an oxide of nitrogen. 3 mol of copper react...
Propene, hydrogen cyanide and carbon dioxide each contain π bonds. Which molecules contain two π bonds?