Cambridge Past Paper Questions
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The compound nitrosyl bromide, NOBr, can be formed by the reaction shown. 2NO + Br₂ ⇌ 2NOBr
The table lists values of solubility products, Ksp, of some Group 2 carbonates. solubility product in water at 298K, Ksp/mol²dm⁻⁶ MgCO₃ 1.0 x 1...
Compound P contains several functional groups. [Figure of Compound P with a benzene ring attached to C(Cl)=C(CN)₂]
(a) 4-nitromethylbenzene can be prepared via an electrophilic substitution reaction as shown. [Figure showing reaction of methylbenzene to 4-nitrom...
Ethanedioate ions, ⁻O₂CCO₂⁻, are bidentate ligands. The abbreviation ed²⁻ can be used to represent ethanedioate ions.
The compound chlorine dioxide, ClO2, can be prepared by the reaction shown. NaClO2 + ½Cl2 → ClO2 + NaCl
When water is added to magnesium nitride, Mg3N2, the products are a white suspension of Mg(OH)2 and an alkaline gas.
Serotonin can be synthesised from the amino acid tryptophan in two steps. [Figure 3.1: Structure of Tryptophan] [Figure 3.2: Structure of Serotonin]
An electrochemical cell consists of a half-cell containing V³+(aq) and V²+(aq) ions and another half-cell containing VO2+(aq) and VO2+(aq) ions.
The arrangement of the anions around a cation is called the geometry of the cation; e.g. in [CuCl4]2- the geometry of copper is tetrahedral and the...
Calcium carbide, CaC2, reacts readily with water, forming ethyne, C₂H₂, and a sparingly soluble white ionic compound. (a)(i) Write an equation for ...
Compound A can be produced from a plant hormone. [Figure 8.1: Structure of Compound A]
The compound nitrosyl bromide, NOBr, can be formed by the reaction shown. 2NO + Br₂ ⇌ 2NOBr (c) The rate of the reaction was measured at various c...
(c) Car batteries are made up of rechargeable lead-acid cells. Each cell consists of a negative electrode made of Pb metal and a positive electrode...
Compound P contains several functional groups. [Figure of Compound P: a benzene ring attached to a C=C double bond. One carbon of the C=C is bonded...
Iodide ions, I⁻, and persulfate ions, S₂O₈²⁻, react according to the following equation. 2I⁻(aq) + S₂O₈²⁻(aq) → I₂(aq) + 2SO₄²⁻(aq) The rate of r...
Dilute sulfuric acid, H₂SO₄(aq), can be electrolysed using platinum electrodes and a direct current. Hydrogen gas is produced at the cathode and ox...
Verdigris is a green pigment that contains both copper(II) carbonate, CuCO3, and copper(II) hydroxide, Cu(OH)2, in varying amounts. Both copper com...
Activated charcoal is a form of carbon with a very high surface area. It can be used to remove impurities from mixtures. It does this by a process ...
Iodide ions, I⁻, and persulfate ions, S₂O₈²⁻, react according to the following equation. 2I⁻(aq) + S₂O₈²⁻(aq) → I₂(aq) + 2SO₄²⁻(aq) The rate of rea...
Which statement about enthalpy changes is correct?
Beams of charged particles are deflected by an electrical field. The angle of deflection of a particle is proportional to its charge/mass ratio. In...
Rubidium and bromine form ions that are isoelectronic. Each ion has 36 electrons. Which row is correct?
In which set do all the molecules have all their atoms arranged in one plane?
Exactly 1.00 g of a metallic element reacts completely with 300 cm³ of oxygen at 298 K and 1 atm pressure to form an oxide which contains O²⁻ ions....
Ammonium metavanadate, NH4VO3, can be used to make a solution containing VO2Cl, which contains chloride ions. What is the change in the oxidation n...
In this question, all pressures are measured in atm. The equation represents the equilibrium between three gaseous substances X, Y and Z. X + 3Y ⇋ ...
In a chemical system the particles involved have a range of energies. This can be shown on a graph called the Boltzmann distribution. Which stateme...
Nitrogen and hydrogen can react together to form ammonia. The formation of ammonia is exothermic. The rate and yield of the reaction can be altered...
The melting points of the Period 3 elements phosphorus to argon are shown in the table. Which factor explains the changes in melting points from ph...
Which observations are made when a sample of silicon chloride, SiCl4, is added to a beaker of water?
A 4.00 g sample of an anhydrous Group 2 metal nitrate is heated strongly until there is no further change. A solid residue of mass 1.37 g is formed...
In which row are all statements comparing magnesium and barium correct?
Which statement about the halogens is correct?
Chlorine reacts with both hot and cold sodium hydroxide to form products containing chlorine. Cold sodium hydroxide forms sodium chlorate(X) and ho...
If ammonium cyanate is heated in the absence of air, the only product of the reaction is urea, CO(NH2)2. No other products are formed in the reacti...
There are three structural isomers with the formula C5H12. Which formulae correctly represent these three structural isomers?
The diagram shows a molecule that has σ bonds and π bonds. [Figure of CH2=CH-CH2—C—O—CH2—CH=CH2] How many σ bonds are present in this molecule?
Polyethene is made by the polymerisation of ethene. Which statement is correct?
Compound P reacts separately with KOH(aq) and HBr. CH2CHCH2CH2Cl compound P What are the mechanisms of these two reactions?
Which statement about compound Q is correct? CH3C=CHCH2CH3 CO2CH3 Q
A halogenoalkane has the molecular formula C5H11Br. The halogenoalkane does not form an alkene when treated with ethanolic sodium hydroxide. What c...
The reactions of four organic compounds are given in the table. Which compound could be propan-2-ol?
Compound X has the empirical formula C2H3O. Compound X reacts with 2,4-dinitrophenylhydrazine reagent to give an orange precipitate and also decolo...
Compound Y gives methanol and sodium ethanoate on treatment with aqueous sodium hydroxide. What is the structure of Y?
Which compound can be used to make propanoic acid by treatment with a single reagent?
The infra-red spectrum of compound L is shown. [Figure X.X] What could be the structure of L?