S.3 Chem Hols Test 1 2020 Caltec S.3

1 NAME:…………………………………………………………………SCHOOL………………………………………. S.3 HOLIDAY CHEMISTRY TEST 3: TIME : 1HOUR 1. State a suitable method of separation of each of the following mixtures. In each case state the underlying principle in each case. a) Bariumnitrate and barium sulphate (1mark) Method ---------------------------------------------------------------------------------------- Underlying principle ---------------------------------------------------------------------------------------- b) Water and petrol (1mark) Method ---------------------------------------------------------------------------------------- Underlying principle ---------------------------------------------------------------------------------------- c) Sodiumcarbonate and sodium hydrogen carbonate. (1mark) Method ---------------------------------------------------------------------------------------- Underlying principle ---------------------------------------------------------------------------------------- d) Iron(III)chloride and sodium chloride (1mark) Method ---------------------------------------------------------------------------------------- Underlying principle ---------------------------------------------------------------------------------------- e) Ethanol and water (1mark) Method ---------------------------------------------------------------------------------------- Underlying principle ---------------------------------------------------------------------------------------- 2. a) Define the term Rusting (1mark) ----------------- ----------------------------------------------------------------------------------------------------------------------------- - ------------------------------------------------- b) i) Write the chemical name and formula of rust. (2marks) ------------------- ---------------------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------- ii) State the conditions necessary for rusting to take place. (1mark) --------------------------------------------------------------------------------------------- c) State two methods of preventing the rusting process. (1mark) --------------------------------------------------------------------------------------------- -------------------------------------------------- 3. Calculate the formula masses of each of the following chemical. a) Ammonium iron(II)sulphate -12-water, (NH 4)2SO 4.FeSO 4.12H 2O. (N=14, H=1, S=32, Fe=56, O=16) ( 2 marks) ----------------------------------------------------------------------------------------------------------------------------- ----------------------- ------------------------------------------------------------------------------------------------------------ ------------ ---------------------------- 2 b) Adipic acid, HOOCCH 2CH 2COOH (C=12,H=1,O=16). (2marks) ----------------------------------------------------------------------------------------------------------------------------- ----------------------- ------------------------------------------------------------------------------------------------------------ ---------------------------------------- -------------------------------------------------------------------------------------------------------------------- ----------------------------- 4.a) Write an ionic equation for the laboratory preparation of carbond ioxide gas. (1 ½ marks) ……………………………………………………………………………………………………………………………… b). State the conditions necessary for the laboratory preparation of carbondioxide.(1mark) ……………………………………………………………………………………………………………………………… c) During the preparation of carbondioxide suggest a reason why the gas is passed through the following. i) Water (1mark) ------------------------------------------------------------------------------------------------ ii) Concentrated sulphuric acid (1mark) ----------------------------------- ---------------------------------------------------------------- d) Write equation for the reaction between heated magnesium ribbon and carbondioxide . (1 ½ marks) ………………………………………………………………………………………………………… …………………… 5. Diamond is one of the crystalline allotropes of carbon and it is widely used as jewellery. (a) State; (i) What is meant by the term “allotrope”. (1mark) ………………………………………………………………………………………………………………………………… ………………………………………………………………………………………………………………………………… ……………………………………………………………………………………… …………………………………. (ii) The property of diamond which makes it useful …