Cambridge & Pearson Edexcel Past Paper Questions
Browse 35,704 questions from Cambridge O-Level & A-Level and Pearson Edexcel IGCSE & IAL exams. Click any question to practice.
Which process could be used to calculate the bond energy for the covalent bond X-Y by dividing its ΔH by n?
In which pair do the molecules have the same shape as each other?
Why is the ionic radius of a chloride ion larger than the ionic radius of a sodium ion?
What are the trends in the stated properties as Group II is descended from magnesium to barium?
Use of the Data Booklet is relevant to this question. The nitrates of beryllium, calcium, magnesium, and strontium all decompose in the same way wh...
In a car engine, non-metallic element X forms a pollutant oxide Y. Y can be further oxidised to Z. Two students made the following statements. Stud...
Use of the Data Booklet is relevant to this question. 1.15 g of a metallic element reacts with 300 cm³ of oxygen at 298 K and 1 atm pressure, to fo...
Elements X and Y are both in period three. When the chloride of X is added to water, it reacts and a solution of pH 2 is produced. When the chlorid...
Which diagram shows the variation of the metallic radius r of the Group I elements, Li, Na, K and Rb, with increasing proton (atomic) number?
Carvone is found in spearmint. [Figure 20.1] How many σ and π bonds are present in this molecule?
An alkene has the formula CH3CH=CRCH2CH3 and does not possess cis-trans isomers. What is R?
Menthol is an important compound extracted from the peppermint plant. [Figure 22.1] How many chiral centres are there in one molecule of menthol?
The cracking of a single hydrocarbon molecule, CnH2n+2, produces two hydrocarbon molecules only. Each hydrocarbon product contains the same number ...
But-2-ene-1,4-diol is converted in two steps through an intermediate X into ketobutanedioic acid. [Figure 24.1] What could be the reagent for step ...
One of the reactions taking place in a catalytic converter in a car exhaust system is between nitrogen oxide and octane (unburned petrol). The prod...
High-energy radiation in the stratosphere produces free-radicals from chlorofluoroalkanes, commonly known as CFCs. Which free-radical is most likel...
Which reagent reacts with ethanol and also reacts with ethanoic acid?
In 1903 Arthur Lapworth became the first chemist to investigate a reaction mechanism. The reaction he investigated was that of hydrogen cyanide wit...
Compound X, C6H12O, is oxidised by acidified sodium dichromate(VI) to compound Y. Compound Y reacts with ethanol in the presence of a little concen...
How may nitrogen exist in compounds? 1 bonded by a triple covalent bond 2 as part of a cation 3 having lost 3 electrons to form an anion
Use of the Data Booklet is relevant to this question. The isotope 99Tc is radioactive and has been found in lobsters and seaweed adjacent to nuclea...
Which of these substances have a giant structure? 1 silicon(IV) oxide 2 baked clay found in crockery 3 phosphorus(V) oxide
The element astatine, At, is below iodine in Group VII of the Periodic Table. Which statements concerning At will be correct? 1 It is a dark-colour...
Which equations represent stages in the Contact process for manufacturing sulfuric acid? 1 SO2 + ½ O2 → SO3 2 SO2 + H2O → H2SO3 3 H2SO3 + ½ O2 → H2SO4
When added to water, which oxides will not cause a change in pH? 1 Al2O3 2 SiO2 3 P4O10
Which reagents and conditions will convert propane into 1-chloropropane? 1 Cl2 and sunlight 2 conc. HCl, reflux 3 PCl5
Chloroethane can be formed from bromoethane in two steps. C2H5Br --(step X)--> C2H5OH --(step Y)--> C2H5Cl Which statements about these steps are c...
Which reagents react with butanone, C2H5COCH3? 1 Tollens' reagent 2 sodium borohydride 3 2,4-dinitrophenylhydrazine reagent
Oleic acid is found in olive oil. It has the following formula. [Figure 40.1] Which reagents will give a positive result with oleic acid? 1 aqueous...
At the age of 17, in a woodshed in Ohio, Charles Martin Hall discovered the commercial process for the production of aluminium metal by the electro...
In which reaction does a single nitrogen atom have the greatest change in oxidation number?
The following half reactions occur when potassium iodate(V), KIO3, in hydrochloric acid solution oxidises iodine to ICl2⁻. IO3⁻ + 2Cl⁻ + 6H⁺ + 4e⁻ ...
Use of the Data Booklet is relevant to this question. In which set do all species contain the same number of electrons?
An autocatalytic reaction is a reaction in which one of the products catalyses the reaction. Which curve was obtained if the rate of reaction was p...
The diagrams below show the Boltzmann distribution for air at two temperatures. The solid line represents the distribution at –20 °C. The dotted li...
Which stage in the free radical substitution of methane by chlorine will have the lowest activation energy?
Use of the Data Booklet is relevant to this question. The approximate percentage composition of the atmosphere on four different planets is given i...
Nitrogen reacts with hydrogen to produce ammonia. N2(g) + 3H2(g) ⇌ 2NH3(g) A mixture of 2.00 mol of nitrogen, 6.00 mol of hydrogen, and 2.40 mol of...
Use of the Data Booklet is relevant to this question. Which sodium compound contains 74.2% by mass of sodium?
Use of the Data Booklet is relevant to this question. A student carried out an experiment to determine the enthalpy change for the combustion of me...
Strontium metal can be obtained by the electrolysis of molten strontium bromide, SrBr2, using the apparatus shown in the diagram. [Diagram of appar...
A metal, X, reacts with water to produce a colourless solution which gives a white precipitate when mixed with aqueous sulfuric acid. What is metal X?
Which property increases in value going down Group II?
Which row correctly identifies the uses of some of the compounds of Group II metals? [Table showing uses in kilns and agriculture for various Group...
Solid potassium halides react with concentrated sulfuric acid, according to the following equations. reaction 1 2KCl + H2SO4 → K2SO4 + 2HCl reactio...
Transition metals and their compounds are used as catalysts. Which row is correct? [Table showing transition metal present in the catalyst used in ...
Consecutive elements X, Y and Z are in the third period of the Periodic Table. Element Y has the highest first ionisation energy and the lowest mel...
A new industrial preparation of ethyl ethanoate has been developed using cheap sources of ethanol. [Reaction scheme: CH3CH2OH → CH3CHO → CH3CH(OH)O...
Which reaction will give the best yield of 1-chloropropane?
The compound 'leaf alcohol' is partly responsible for the smell of new-mown grass. CH3CH2CH=CHCH2CH2OH leaf alcohol What will be formed when ‘leaf ...