​The cell convention for an electrochemical cell is shown below

​a) Name two substances that can be used as electrolytes in the above cell (2mks)

​b) Which of the electrodes is the anode? (2mks)

​Define oxidation and reduction in terms of electrons

​a) The solubility of the salt (2mks)

​b) The percentage of the salt in the saturated solution  (1mk)

The following diagram represents a charcoal burner. Study it and answer the questions that follow

​Write the equations for the reaction at; (3mks)

A

B

C

Study the experiment above and answer the questions that follow. The gas produced ignites spontaneously

i) Which metal is used above (1mk)

ii) Which gas was produced (1mk)

​iii) What will be the colour of phenolphthalein indicator in the resulting solution? (1mk)

​Name one gas used together with oxygen in welding other than acetylene gas (1mk)

State two other uses of the gas named above (2mks)

​The result is shown below;

​i) Which ink was contaminated with substance P (1mk)

​ii) Name the ink which was pure (1mk)

​iii) Identify the other ink which was not pure (1mk)

When a certain hydrocarbon burnt completely in excess oxygen 5.28g of Carbon (IV) oxide and 2.16g of water were formed. If the molecular mass of the hydrocarbon is 84, determine the molecular formula of the hydrocarbon ​

Using dots (•) and cross (x) show the formation of Carbon (II) oxide gas (1mk)

Name two types of bonds present in the molecule in ‘a’ above (2mks)

​Name three sub – atomic particles found in an atom and state where they are found (3mks)

​a) How do their rate of diffusion compare? (2mks)

b) Determine the relative molecular mass of X given that the relative molecular mass of Y is 64 (1mk)

​a) Sugar crystals. (1mk)

​b) Hydrated copper (II) sulphate solution (1mk)

​c) What type of reaction has taken place above (1mk)

​a) State Charles’s law (1mk)

​b) Calculate the volume of the gas at 77-mmHg pressure (2mks)

Calculate the volume of the gas at 77-mmHg pressure