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.
The reaction between 1-chloro-1-phenylethane and hydroxide ions to produce 1-phenylethanol is: C₆H₅CH(Cl)CH₃ + OH⁻ → C₆H₅CH(OH)CH₃ + Cl⁻ 1-chloro-1...
Describe and explain the variation in the thermal stabilities of the carbonates of the Group 2 elements.
Complete the table to show how both AgNO3(aq) and NH3(aq) could be used to distinguish between solutions of NaCl(aq) and Nal(aq). test performed o...
In a molecule of SOCl2 the sulfur atom has four bonds. Draw a 'dot-and-cross' diagram of SOCl2. Show the outer shell electrons only.
A number of isomers with the formula Cr(H2O)6Cl3 exist. Their general formula is [Cr(H2O)6-nCln]Cl3-n.nH2O. Each isomer contains a six co-ordinated...
1,2-diaminoethane, en, H2NCH2CH2NH2, is a bidentate ligand.
The table lists some organic acids and their pKa values. acid formula pKa ethanoic acid CH3CO₂H 4.76 chloroethanoic acid CICH₂CO₂H 2.86 aminoet...
Compounds W, X, Y and Z are isomers of each other with the molecular formula C｡H,CIO. All four isomers contain a benzene ring. Only one of the isom...
The amino acid tyrosine can be synthesised from phenol by the route shown. OH step 1 CHO step 2 CN HO HO phenol HO step 3 NH2 Cl OH step 5 s...
The table lists the standard enthalpy changes of formation, ΔH, for some compounds and aqueous ions. | species | ΔHᶠ/kJ mol⁻¹ | |------------|-...
The pain of muscle strains and swellings can be eased by using heat packs. As a source of heat, some heat packs use the energy released when anhydr...
Sucrose is a sugar. The concentration of a solution of sucrose can be measured by the optical rotation, α, of a sucrose solution. The more concentr...
In 1804 the chemist John Dalton put forward the following idea. It is sometimes called 'Dalton's Law'. 'When two elements combine with each other ...
When light passes through solutions of chemical compounds some of the light may be absorbed. The quantity of light absorbed is called the absorbanc...
Which feature is present in both ethene and poly(ethene)?
The electronic configuration of an atom of sulfur is 1s²2s²2p⁶3s²3p⁴. How many valence shell and unpaired electrons are present in one sulfur atom?...
In which pair does the second substance have a lower boiling point than the first substance?
Compound J burns in excess oxygen to give carbon dioxide and water only. When a 3.00 g sample of compound J is burnt in excess oxygen, 4.40 g of ca...
The gases X and Y react to form Z. X(g) + Y(g) ⇌ Z(g) An equilibrium mixture of these three gases is compressed at constant temperature. What will ...
Which gas is likely to deviate most from ideal gas behaviour?
The enthalpy change of reaction 1 is –114 kJ mol⁻¹. 2NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + 2H2O(l) reaction 1 By using this information, what is the ...
Sulfur reacts with concentrated nitric acid in a redox reaction. S + 4HNO3 → SO2 + 4NO2 + 2H2O What are the changes in oxidation number of sulfur a...
Materials can be classified by their chemical structures. Four common types of structure are metallic, ionic, simple molecular and giant molecular....
In a particular reversible reaction the yield of product is increased • if the temperature is increased; • if the pressure is decreased. Which equa...
A chemical company used a catalyst in a chemical process. The company has now decided not to use the catalyst but to increase the temperature so th...
Which oxide does not react with cold, dilute sodium hydroxide to produce a salt?
The graphs show trends in four physical properties of elements in Period 3, excluding argon. Which graph has electronegativity on the y-axis? [Grap...
In this question, X represents an atom of chlorine, bromine or iodine. Which explanation for the variation in volatility down Group 17 is correct?
To manufacture cement, 1000 million tonnes of limestone are decomposed each year. To manufacture lime for agriculture, 200 million tonnes of limest...
When concentrated sulfuric acid is added to solid sodium bromide, bromine gas is produced, along with a number of other products. However when conc...
The dative covalent bond can be represented by an arrow, →. The arrow points towards the atom receiving the lone pair. Which diagram of an ammonium...
Sulfur dioxide can be catalytically oxidised by an oxide of nitrogen in the atmosphere. Which reaction shows the regeneration of the catalyst?
Compound Y is treated with an excess of hydrogen gas in the presence of a nickel catalyst. The product is fully saturated. [Diagram of compound Y] ...
Which equation represents a valid propagation step in the chlorination of ethane?
Maleic acid is used in the food industry and for stabilising drugs. It is the cis-isomer of butenedioic acid and has the structural formula HO2CCH=...
Primary halogenoalkanes undergo hydrolysis reactions. Which reaction would occur most rapidly if they are all warmed to the same temperature?
Structural isomerism and stereoisomerism should be considered when answering this question. A colourless liquid, C5H11Cl, exists as a mixture of tw...
When warm water is added to halogenoalkane X, an SN1 reaction occurs. AgNO3(aq) is then added; a yellow precipitate is formed. What could be X?
Which statement about butanone is correct?
Ethanal, CH3CHO, is used to make product R in a three-stage synthesis. CH3CHO →product P (HCN/NaCN) →product Q (H2SO4(aq), reflux) →product R (conc...
The infra-red spectrum of an organic compound is shown. [Infra-red spectrum graph] Which compound could give this spectrum?
For complete combustion, 1 mol of an organic compound X requires 2.5 mol of O2. Which compounds could be X? 1 C2H5OH 2 C2H2 3 CH3CHO
In which pairs do both species have the same number of electrons? 1 ³⁵Cl and ³⁷Cl 2 ³⁵Cl⁻ and ⁴⁰Ar 3 ⁴⁰Ar and ⁴⁰K⁺
For which reactions does the value of ∆H represent both a standard enthalpy change of combustion and a standard enthalpy change of formation? 1 C(s...
The temperature of a reversible gas phase reaction is increased. Which statements are always correct? 1 More product is present at equilibrium. 2 T...
Three samples of chlorine gas each contain 0.710g of chlorine. Each sample is reacted with a reagent. • In the first reaction a sample is reacted c...
Solid barium oxide is added to some ammonium sulfate solution in a test-tube and the mixture is warmed. A piece of damp red litmus paper is held ov...
Which compounds show geometrical (cis-trans) isomerism? 1 CH3CH=C(CH3)C2H5 2 CH3CH=CHCH2CH2CH3 3 C2H5CH=CHC2H5
Which pairs of compounds may be distinguished from each other by testing with alkaline aqueous iodine? 1 ethane-1,2-diol and ethanol 2 propan-2-ol ...
The diagram shows an experimental set-up which can be used in several different experiments. [Diagram of experimental set-up] Which processes could...