1.28 Compound X, C4H8O2, has an unbranched carbon chain. An aqueous solution of X has an approximate pH of 3.   Compound Y, C3H8O, is a secondary alcohol. X and Y are reacted together in the presence of a little concentrated sulfuric acid to form Z as the major organic product.   What is the structural formula of Z?   A (CH3)2CHCO2CH2CH2CH3 B CH3(CH2)2CO2CH(CH3)2 C CH3(CH2)2CO2(CH2)2CH3 D (CH3)2CHCO2CH(CH3)2

1.33 What are the ionic half-equations for the electrode reactions during the electrolysis of concentrated aqueous sodium chloride?   

  QUESTION 6   The graph shows how the temperature of a substance changes as it is cooled over a period of 30 minutes. The substance is a gas at the start.   Right-click on the button to open the data booklet in a new tab.        Each letter on the graph may be used once, more than once or not at all. State when:   6.1 the particles in the substance have the most kinetic energy? [1] 6.2 the particles in the substance are furthest apart? [1] 6.3 the substance exists as both a gas and a liquid? [1] 6.4 The moment that all the substance is solid? [1] 6.5 Use the graph to estimate the freezing point of the substance. [1] 6.6 Name the change of state directly from a solid to a gas. [1]   When smoke is viewed through a microscope, the smoke particles in the air appear to jump around.   6.7 What term describes this movement of the smoke particles? [1] 6.8 Explain why the smoke particles move in this way. [2]     [9]

1.31 Which statement describes the structure of copper?  

1.24 The diagram shows a cup of hot tea.   Right-click on the button to open the data booklet in a new tab.        Which row describes the water particles in the air above the cup compared with the water particles in the cup?   Moving faster Closer together A Yes No B Yes Yes C No No D No Yes

1.32 Calcium carbonate reacts with dilute hydrochloric acid. The equation for the reaction is shown. CaCO3 + 2HCl — > CaCl 2 + H2O + CO2 1.00 g of calcium carbonate is added to 50.0 cm3 of 0.0500 mol / dm3 hydrochloric acid. Which volume of carbon dioxide is made in this reaction?

1.35 Carbonic acid is a weak acid formed when carbon dioxide dissolves in water. What is the pH of the solution?

1.30 A method used to investigate the rate of reaction of calcium carbonate with dilute hydrochloric acid under different conditions is shown.   ● Place 50 cm3 of dilute hydrochloric acid in a conical flask. ● Add a known volume of water to the conical flask. ● Heat the conical flask to the required temperature. ● Add 1.0 g of calcium carbonate to the conical flask. ● Measure the time taken for the reaction to finish.   Which volume of water and which temperature gives the shortest time taken for the reaction to finish?     volume of water added / cm3 temperature / °C A 10 30 B 10 50 C 40 30 D 40 50

1.17 Which properties of the element titanium, Ti, can be predicted from its position in the Periodic Table?     can be used as a catalyst   conducts electricity when solid has low density   forms coloured compounds   A Yes Yes No Yes B Yes Yes Yes No C Yes No Yes Yes D No Yes Yes Yes

1.13 Aqueous potassium iodide is added to aqueous silver nitrate.What are the colours of the final precipitate and solution?