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.
In an experiment, 0.600 mol of chlorine gas, Cl₂, is reacted with an excess of hot aqueous sodium hydroxide. One of the products is NaClO₃. Which m...
Z is an anhydrous compound of a Group 2 element. When it is heated, Z undergoes thermal decomposition to produce two different gases. Z has relativ...
Methylamine, CH₃NH₂, has very similar chemical properties to ammonia, NH₃. Methylamine reacts with hydrogen chloride to form a white crystalline sa...
Structural isomerism and stereoisomerism should be considered when answering this question. How many isomers with the formula C₄H₈ have structures ...
Kerosene is used as an aircraft fuel. Q is one of the molecules in kerosene and has the skeletal formula shown. [Figure showing skeletal formula of...
Which radical is most likely to form by the homolytic fission of one covalent bond in bromochloromethane, CH₂BrCl?
Propene undergoes a variety of reactions. Which row is correct?
Polymerisation of ethene gives poly(ethene). How does the bonding between carbon atoms in poly(ethene) compare with that in ethene?
Diols in which both hydroxy groups are bonded to the same carbon can spontaneously eliminate a molecule of water to produce a carbonyl compound. Wh...
Propan-2-ol undergoes many reactions. Which row is correct?
Ethane-1,2-diol has the following structure. [Figure showing HO-CH₂-CH₂-OH]. Without breaking the C-C bond, there are five possible oxidation produ...
CH₃CH₂COCH₂CH₃ reacts with hydrogen cyanide to form an organic product called a cyanohydrin. Which statement is correct?
Compound X, CH₃CH(OH)CH(CHO)CH₃, is heated under reflux with an excess of acidified K₂Cr₂O₇ to form compound Y. Both X and Y are separately warmed ...
Which two compounds can react together to produce an ester?
Nitrogen and phosphorus are both in Group 15 of the Periodic Table. Phosphorus forms a chloride with the formula PCl₅ but nitrogen does not form NC...
When a sample of a gas is compressed at constant temperature from 1500 kPa to 6000 kPa, its volume changes from 76.0 cm³ to 20.5 cm³. Which stateme...
Which of these statements are always correct? 1 The sum of the oxidation numbers of all the atoms in a compound is zero. 2 The oxidation number of ...
Sulfur dioxide and oxygen react in the gas phase. 2SO₂(g) + O₂(g) ⇌ 2SO₃(g) ∆H = –197 kJ mol⁻¹ Which statements are correct? 1 Increasing the press...
Three test-tubes, X, Y, and Z, each contain a small amount of water. • A small amount of NaCl is added to test-tube X. • A small amount of SiCl₄ is...
Sodium chloride and sodium iodide react with concentrated sulfuric acid. Which statements are correct? 1 Sodium chloride is not oxidised by concent...
Which compounds can be obtained from but-2-ene in a single reaction? 1 CH₃CH(OH)CH(OH)CH₃ 2 CH₃CH(OH)CH₂CH₃ 3 CH₃CO₂H
Which statements help to explain the mechanism of the reaction between 1-chloropropane and ammonia? 1 1-chloropropane has a δ− chlorine atom that f...
Which compounds react with alkaline aqueous iodine to give a pale yellow precipitate of tri-iodomethane? 1 butanone 2 ethanal 3 propan-2-ol
Propanoic acid occurs naturally as a result of the bacterial fermentation of milk and is partly responsible for the flavour of Swiss cheese. [Figur...
(a) The table shows information about some of the elements in the third period. element | Na | Mg | Al | P | S | Cl ---|---|---|---|---|---|--- at...
Hydrogen halides are compounds formed when halogens (Group 17 elements) react with hydrogen. The bond polarity of the hydrogen halides decreases fr...
(a) A series of reactions starting from 1-bromobutane is shown. [Figure showing reaction scheme: 1-bromobutane reacts with HCN and KCN to form P, t...
The concentration of hydrogen peroxide may be given in moldm-³ or as 'volume strength'. You will determine the concentration of hydrogen peroxide i...
You will carry out a second experiment to determine the concentration of hydrogen peroxide, FA 1, in moldm⁻³, by titration with acidified aqueous p...
Qualitative Analysis At each stage of any test you are to record details of the following. • colour changes seen • the formation of any precipitate...
The mass spectrum of silicon is shown. [Diagram: A mass spectrum showing relative intensity on the y-axis (up to 1.0) and m/e on the x-axis (from 2...
Complete the table using ticks (√) to indicate whether the sign of each type of energy change, under standard conditions, is always positive, alway...
(a) The diagram shows the apparatus used to measure the standard electrode potential, E°, of Fe³⁺(aq)/Fe²⁺(aq). [Figure showing apparatus for stand...
(a) Chlorine dioxide undergoes the following reaction in aqueous solution. 2ClO₂ + 2OH⁻ → ClO₂⁻ + ClO₃⁻ + H₂O The initial rate of the reaction was ...
(a) Compound H can be synthesised from benzene as shown. [Figure: Reaction scheme starting from benzene, going through step 1, then intermediate G,...
(a) (i) Draw the shape of one of the d orbitals.
The compound Advantame is a sweetener that tastes approximately 25000 times sweeter than sucrose. [Figure: Structure of Advantame (C23H29NO4)]
The root of the ginger plant contains compounds with medicinal and flavouring properties. Three of the more important compounds are gingerol, shoga...
This question is about compound T, CₓH_yO₂. (a) Part of the mass spectrum of T is shown. The peak heights of the M and M+1 peaks are 33.9 and 3.4 r...
The enthalpy change of reaction, ∆H, for the decomposition of sodium hydrogencarbonate, NaHCO3(s), cannot be measured directly. 2NaHCO3(s) → Na2CO3...
Transition metal complex ions are coloured. The formula of a complex ion can be determined using colorimetry. In colorimetry, light of a certain wa...
What are the shapes of the molecules of water and boron trifluoride?
The electronic configuration of the two outermost shells of an atom is 3s²3p³3d⁵4s². What is this atom?
Drinking water may contain dissolved calcium hydrogencarbonate, Ca(HCO₃)₂. How many electrons are present in a hydrogencarbonate anion?
Which molecule contains a nitrogen atom with sp hybridised orbitals?
Which mass of solid residue is obtained from the thermal decomposition of 4.10 g of anhydrous calcium nitrate?
Sodium hydroxide neutralises acid. H⁺ + OH⁻ → H₂O In a 11000 dm³ sample of an aqueous solution, the concentration of acid, [H⁺], is 1.26 x 10⁻³ mol...
The gas laws can be summarised in the ideal gas equation. pV = nRT 0.960 g of oxygen gas is contained in a vessel of volume 7.00 × 10⁻³ m³ at a tem...
Which equation represents the standard enthalpy change of formation of water?
Hess' Law and bond energy data can be used to calculate the enthalpy change of a reaction. Bromoethane, CH₃CH₂Br, can be made by reacting ethene wi...