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.
Explain what is meant by the term entropy of a system.
Phenylethanone is an important chemical with many uses. phenylethanone [Figure of phenylethanone structure]
The structure of butamben is shown. butamben [Figure of butamben structure]
Yttrium barium copper oxide, YBa₂Cu3O7, is a crystalline compound. You are to design an experiment in which YBa₂Cu3O7 is first synthesised and then...
The viscosity of a substance is a measure of how quickly the substance flows when it is subjected to a force such as gravity. The viscosity of a li...
Many organic reactions performed in the laboratory require heating under reflux. 4-nitromethylbenzene can be converted directly to 4-aminobenzaldeh...
Naphthalene, C₁₀H₈, is an aromatic organic compound that is a solid at room temperature and pressure. The enthalpy change of fusion, ∆Hfusion, of n...
What is the average oxidation number of sulfur in each compound?
An ore of manganese contains 4% by mass of MnO₂ and no other manganese compound. Which mass of manganese would be obtained from 1 tonne of this ore?
Which atomic orbitals are occupied in an atom of phosphorus?
The structure of compound A is shown. [Figure 4.1] Some of the carbon atoms in compound A have a tetrahedral arrangement of bonds. Some of the carb...
A white powder is known to be a mixture of magnesium oxide and aluminium oxide. 100 cm³ of 2 mol dm⁻³ NaOH(aq) is just enough to dissolve the alumi...
A graph of pV against T is shown for a fixed mass of gas. (p = pressure, V = volume and T = temperature in K.) [Figure 6.1] Which gas gives this gr...
A weather balloon is filled with 12.0 kg helium. The weather balloon reaches a height of 20 km, the pressure inside the balloon is 6000 Pa and the ...
Which pair of enthalpy changes will always share the same sign (i.e. both are always exothermic or both are always endothermic)?
Chlorine dioxide, ClO₂, reacts with sodium hydroxide in the reaction shown. 2ClO₂ + 2OH¯ → ClO₂⁻ + ClO₃⁻ + H₂O Which statement correctly describes ...
Sulfur dioxide and oxygen react to form sulfur trioxide. The reaction is reversible. 2SO₂(g) + O₂(g) ⇌ 2SO₃(g) Kp = 2.96 × 10⁻⁹ Pa⁻¹ at 700 °C The ...
Ammonia is made by the Haber process. The reactants are nitrogen and hydrogen. N₂(g) + 3H₂(g) ⇌ 2NH₃(g) ΔH is negative What will increase the rate ...
Which row could refer to barium metal and barium hydroxide?
AgNO₃(aq) is added to a solution of a halide ion, X⁻(aq), and aqueous ammonia is then added. The ionic equations for the two reactions that occur a...
Due to their similar ionic radii, the reactions of lithium and magnesium and their corresponding compounds are very similar. Which statement about ...
Which statement about Group 17 elements and their compounds is correct?
Which substance, when warmed with aqueous ammonium chloride, would produce an alkaline gas?
Compound X is the oxide of a Period 3 element. Compound X reacts with water to give an acidic solution. A solution is prepared by reacting 0.100 g ...
The unsaturated hydrocarbon octa-1,3,5,7-tetraene, C₈H₁₀, can display geometric isomerism. octa-1,3,5,7-tetraene CH₂=CHCH=CHCH=CHCH=CH₂ How many is...
What is the correct name for the compound shown? [Figure 21.1]
A polymer has the following repeat unit. It is made from two different monomers. [Figure 22.1] Which pair of monomers could be used to make this po...
Compound X contains two functional groups. [Figure 23.1] Which reagent will react with only one of the functional groups?
Ethanol can be converted into ethene in a single reaction. Ethanol can be converted into bromoethane in a single reaction. Under standard laborator...
Diols in which both hydroxy groups are bonded to the same carbon atom can spontaneously eliminate a molecule of water to produce a carbonyl compoun...
Which alcohol will give a yellow precipitate when warmed with alkaline aqueous iodine?
How many structural isomers are there of molecular formula C₅H₁₀O that give a red precipitate with Fehling's solution?
Which statement about the use of alkane fuels in internal combustion engines is correct?
Compound Z is shown. [Figure 29.1] What is produced in good yield when compound Z is treated with an excess of sodium carbonate solution at room te...
The infra-red spectrum shown was obtained from compound G. [Figure 30.1] What could be compound G?
The symbol for a phosphorus ion is ¹⁵³³P³⁻. The symbol for a potassium ion is ¹⁹³⁷K⁺. What do these two ions have in common? 1 the same number of e...
The repeat unit of a polymer is shown. [Figure 32.1] Which types of intermolecular forces exist in the solid polymer? 1 temporary dipole – induced ...
The diagram illustrates the enthalpy changes of a set of reactions. [Figure 33.1] Which statements are correct? 1 The enthalpy change for the trans...
Which statements about a reaction that has reached dynamic equilibrium are correct? 1 The rate of the forward reaction equals the rate of the rever...
Group 2 elements and their compounds show trends in their physical and chemical properties. Barium is above radium in Group 2 of the Periodic Table...
Which statements are correct? 1 The empirical formula of silicon(IV) oxide is SiO₂. 2 The molecular formula of phosphorus(V) oxide is P₂O₅. 3 Silic...
Which reagents could be used, under suitable conditions, to oxidise CH₃CH₂CH₂OH to CH₃CH₂CHO? 1 acidified potassium manganate(VII) 2 acidified pota...
Which free radicals can be generated during a free-radical substitution reaction between chlorine and ethane? 1 CH₃• 2 CH₂ClCH₂• 3 CH₃CCl₂•
Which substances have molecular formula C₄H₈O? 1 [Diagram 1] 2 [Diagram 2] 3 [Diagram 3]
Which reactions produce pentanoic acid? 1 CH₃CH₂CH₂CH(OH)CH₃ + H⁺/MnO₄⁻(aq) 2 CH₃OCO(CH₂)₃CH₃ + HCl(aq) 3 CH₃(CH₂)₃CN + H₂SO₄(aq)
The graph shows the first ionisation energies of some of the elements in Group 2. [Figure 1.1]
Phosphorus, sulfur and chlorine can all react with oxygen to form oxides.
The reducing agent LiAlH4 can be synthesised by reacting aluminium chloride with lithium hydride, LiH.
Iodine is used in many inorganic and organic reactions.
Atoms contain the subatomic particles electrons, protons and neutrons. Protons and electrons were discovered by observations of their behaviours in...