QUESTION 4 4.1 Sulphur dioxide reacts with aqueous…

  QUESTION 4 4.1 Sulphur dioxide reacts with aqueous sodium sulphite to produce a compound with the following composition by mass: 29.1% Na, 40.5% S and 30.4% O. Calculate the empirical formula of this compound.   [3] 4.2 Sulphur dioxide is a toxic gas.     State one environmental reason why sulphur dioxide should not be released into the atmosphere. [1] 4.3 Describe the test for sulphur dioxide. test … observations …   [2]       [6]

  QUESTION 2     This question is about ions and i…

  QUESTION 2     This question is about ions and ionic compounds.   2.1   Choose from the following list of ions to answer the questions.   Br-          Ca2+            Cl –           Cr 3+           Cu 2+ K +                Li +               Na+                 SO32-           SO42-     Each ion may be used once, more than once or not at all. State which ion:     a gives a lilac colour in a flame test. [1]   b forms a grey-green precipitate with aqueous ammonia. [1]   c forms a white precipitate with aqueous sodium hydroxide. [1]   d forms a cream precipitate with acidified aqueous silver nitrate. [1]   e forms a white precipitate with acidified aqueous barium nitrate. [1] 2.2   Describe how to do a flame test on a sample of a salt. [2] 2.3   Magnesium phosphate contains magnesium ions, Mg2+ , and phosphate ions, PO43- . Deduce the formula of magnesium phosphate. [1]       [8]  

1.29 Which statements about endothermic reactions are co…

1.29 Which statements about endothermic reactions are correct?   1 The energy of the products is greater than the energy of the reactants. 2 The energy of the reactants is greater than the energy of the products. 3 The temperature of the surroundings increases during the reaction. 4 The temperature of the surroundings decreases during the reaction.

1.10 The diagram shows that two gases are formed when co…

1.10 The diagram shows that two gases are formed when concentrated hydrochloric acid is electrolysed using inert electrodes.   Right-click on the button to open the data booklet in a new tab.        Which row correctly describes the colours of the gases at the electrodes?   anode (+ve) cathode (–ve) A colourless colourless B colourless yellow-green C yellow-green colourless D yellow-green yellow-green