AJC_H1 chem Paper 1

AJC\H1 chem Paper1\2008 1 Section A For each question there are four possible answers, A, B, C, and D. Choose the one you consider to be correct. 1 0.18 g of a dibasic acid (Mr = 90) is reacted with 0.10 mol dm -3 sodium hydroxide solution. What is the volume of the alkali needed for complete reaction? A 30 cm 3 B 40 cm 3 C 50 cm 3 D 60 cm 3 2 A gaseous organic compound, X, was burnt in an excess of oxygen. A 0.224 dm 3 sample of X, measured at s.t.p., produced 2.2 g of carbon dioxide. How many carbon atoms are there in one molecule of X? A 2 B 3 C 4 D 5 3 If the relative atomic mass of an element which consists of two isotopes 10 M and 11 M is 10.8, what is the percentage of 11 M atoms in the isotopic mixture? A 20 B 50 C 80 D 92 4 Ions of two isotopes of chlorine are 35 Cl - and 37 Cl -. Which one of the following statements is correct? A The 37 Cl - has more protons than 35 Cl -. B The 37 Cl - has more neutrons than 35 Cl -. C The 37 Cl - has more electrons than 35 Cl -. D The electron arrangement of both these ions is 1s 22s 22p 63s 23p 5 5 For whch of the following is the lattice energy likely to have the greatest numerical value (i.e. greatest magnitude, disregarding the sign)? A lithium fluoride C potassium iodide B rubidium chloride D sodium chloride 6 From which of the following reactions can the bond energy of the C—Cl bond be determined by using only the standard enthalpy change of the reaction? A CCl 4 (g) → C(g) + 4Cl(g) B CCl 4 (g) → CCl 2(g) + Cl 2(g) C CCl 4 (g) → C(s) + 2Cl 2(g) D CCl 4 (s) → CCl 4 (g)

AJC\H1 chem Paper1\2008 2 7 Which one of the statements about the properties associated with ionic and covalent substances is correct? A All covalent compounds have low melting points compared to ionic compounds. B Any covalent compound that contain both hydrogen and oxygen in its molecule can form intermolecular hydrogen bonds. C A covalent compound cannot be an electrolyte. D Ionic compounds differ from metals in that ionic compounds do not conduct electricity in the solid state. 8 Which of the following statements best explains why the boiling point of ethanal is higher than that of propane? A The C=O bond in ethanal is stronger than the bonds present in propane molecules. B The dipole-dipole interaction between ethanal molecules is stronger than the Van der Waals forces between propane molecules. C The relative molecular mass of ethanal is higher than that of propane. D The ethanal molecule has a larger surface area than that of propane. 9 V and W can react together to reach equilibrium in the reaction below. V(g) + W(g) X(g) + Y(g) In an experiment, an 1.0 mole each of V and W were reacted at constant pressure P and temperature 350 OC. The amount of Y present in the mixture at intervals of time was recorded. The experiment was repeate