1.1 Which formula shows the way in which atoms are bonded in a molecule butdoes not show all the bond lines?A. EmpiricalB. MolecularC. StructuralD. Condensed structural (2) 1.2 Which ONE of the following compounds has hydrogen bonds between itsmolecules?A. CH3(CH2)2CH3B. CH3COCH2CH3C. CH3COOCH2CH3D. CH3CH(OH)CH2CH3 (2) 1.3 Consider the compound below. Which ONE of the following is … Read more
10.1 The incomplete equations below show the four steps involved in the industrial preparation of sulphuric acid (H2SO4). A and B represent two compounds. Write down the NAME or FORMULA of:10.1.1 Compound A (1) 10.1.2 Compound B (1) 10.1.3 The catalyst used in Step II (1) The sulphuric acid formed in Step IV is used … Read more
The diagrams below show two electrochemical cells in which carbon electrodes are used. In cell A, concentrated copper (II) chloride solution is used and in cell B, liquid aluminium oxide is used. 9.1 What type of electrochemical cell, ELECTROLYTIC or GALVANIC, is shownabove? Give a reason for the answer. (2) 9.2 Write down the:9.2.1 Half-reaction … Read more
8.1 When a piece of sodium metal (Na) is added to water in a test tube, hydrogen gas is released. When phenolphthalein indicator is added to the test tube, the solution turns pink. 8.1.1 Define the term reduction in terms of electron transfer. (2) 8.1.2 Write down the reduction half-reaction. (2) 8.1.3 Write down the … Read more
Learners prepare a solution of known concentration by dissolving 2 g pure sodium hydroxide crystals, NaOH, in water in a 250 cm3 volumetric flask.7.1 Write down the term for the underlined phrase. (1) 7.2 Calculate the:7.2.1 Concentration of the sodium hydroxide solution (4) 7.2.2 pH of the solution (4) The learners now react 1,5 g … Read more
Pure hydrogen iodide gas, HI(g), of concentration 1 mol∙dm-3 , is sealed in a 500 cm3container at temperature T. The reaction reaches equilibrium according to the following balanced equation: 6.1 Define the term chemical equilibrium. (2) 6.2 The graph below shows how the concentrations of the reactant and products vary with time during the reaction. … Read more
1.1 Which ONE of the following compounds has hydrogen bonds betweenmolecules?A. PentanalB. Pentan-2-oneC. Pentanoic acidD. Methyl butanoate (2) 1.2 To which homologous series does a compound with molecular formulaC6H12O2 belong?A. KetonesB. AlcoholsC. AldehydesD. Carboxylic acids (2) 1.3 Which functional groups are involved in the formation of esters?A. Formyl and carbonylB. Hydroxyl and carbonylC. Hydroxyl and … Read more
When light of various frequencies is incident on the metal cathode of a photocell,photoelectrons are emitted from the surface of the cathode.The graph below shows the relationship between the maximum kinetic energy (Ek(max))of an emitted photoelectron and the wavelength of the incident light. 10.1 Use the graph to determine the maximum kinetic energy of the … Read more