Chemistry Department. Standard Grade Homework Exercise Booklet

Transcription

1 Chemistry Department Standard Grade Homework Exercise Booklet Instructions The purpose of this booklet is to help you revise previous work and improve your knowledge & understanding, to maximise your success in Chemistry Pupils should complete one exercise per week, as directed by their teacher. Pupils will have one week to complete the exercise, this is to enable you to seek help if having trouble. DO NOT leave blanks. Exercises should be completed in homework jotters. Notes should be used to complete these exercises.

2 Exercise (a) Give an example of a halogen (b) Give an example of a noble gas (c) Give an example of an alkali metal (d) Give an example of a liquid element (). State ways to speed up a chemical reaction (). Write the formulae for the following compounds Magnesium Bromide Calcium Carbonate Iron(III) Sulphate () (a) Draw the structural formulae for Butene and Cyclobutane (b) Write the molecular formula for each molecule (c) What name is given to molecules with same molecular formula but different structural formula? (d) Which of the molecules would decolourise bromine solution? Explain your answer (6) Exercise Draw a diagram of an atom, showing the position of the nucleus, electrons, neutrons and protons. (). The two most common types of chlorine atom are: 5 7 7Cl and 7Cl a) What name is given to atoms with the same atomic no. but different mass no.? b) Write down the no. of electrons, neutrons and protons in each atom. (). (a) Name the process used to separate crude oil into fractions (b) Crude oil is mainly made up of hydrocarbons. What is a hydrocarbon? (c) What is the definition of a fuel? (d) Why is it dangerous to burn a fuel in a poorly ventilated room?

3 (e) What gas is used up when something is burned? (f) Write the balanced chemical equation for the combustion of methane. (7) Exercise (a) Identify the ionic substances. (b) Identify the substance which exists as a covalent network.. (c) Explain your answer to (b) (a) Identify the hydrocarbons which would quickly decolourise bromine solution. (b) Identify the isomer of the hydrocarbon in box D which belongs to a different homologous series.. Write chemical formula for (a) oxygen (b) sulphur trioxide (c) Iron (III) oxide Exercise Describe the test for oxygen gas. (b) Explain why this test is not positive with air.. (Unit : Hydrocarbons) (a) The fuel used in a Bunsen burner is methane, CH. What is meant by the term fuel? (b) Methane burns to form carbon dioxide and water. (i) Balance this equation: CH + O CO + H O (ii) Name another product which could be formed in Flame A (air hole half closed). (c) Draw a diagram to show the shape of a methane molecule.

4 . Zinc reacts with hydrochloric acid to produce hydrogen gas. (a) State the test for hydrogen gas. (b) During the experiment, the test tube becomes warm. What term is used to describe a reaction which gives out heat? (c) Plot a line graph of the results of the reaction. (d) Predict the volume of gas which would have been given off after 60s. (e) What could be done to the reaction conditions to increase the rate of the reaction? Exercise 5 (a) Identify the particle which is a positive ion. (b) Identify the particles which are isotopes (c) Calculate the number of protons, electrons and neutrons in the following:

5 7 (i) Al (ii) N - 7. Write chemical formula for (i) Sulphur trioxide (ii) Aluminium carbonate. (a) Write the molecular formula for compound A. (b) why can compound B be described as an isomer of compound A? (c) Name the products formed when these compounds are completely burned in a plentiful supply of oxygen. Exercise 6 Ethyne is the first member of a homologous series of compounds called the alkynes. All the alkynes contain Carbon to Carbon triple bond. (a) Give the name of A and write the molecular formula for B. A B (b) Draw the full structural formula for ethyne (c) Deduce the general formula for the alkynes. (C n H? ). (a) (b) (c) 5

6 Exercise 7 (a) (b) (c) (a) Explain why a d.c. supply is used. (b) Write ion electron equations to show the reaction at the (i) positive electrode (ii) negative electrode. (Use p.7 of the data booklet) (c) Why does the copper chloride have to be in a solution before it can be electrolysed? (d) Why couldn t you electrolyse a glucose solution? 8. (a) Describe how nitrogen dioxide is formed in the car engine. (b) What environmental problem does nitrogen dioxide cause? 6

7 Which of the following compounds contains only elements? A Magnesium hydroxide B Magnesium phosphate C Magnesium sulphite D Magnesium nitride. Identify the slowest reaction: Exercise 8. Which element is an alkali metal? A Mg powder + mol/l acid B. Mg (Unit ribbon d) + mol/l acid 0 - C 5. Mg A powder new air + bag mol/l is being acid developed for use (i) in Ca cars. (ii) In the P reaction, 0 5 D butane Mg ribbon reacts + mol/l with acid an oxide of nitrogen: C H 0 + N O CO + H O + N. A B C D Aluminium Calcium Copper Sodium Calculate the number of protons, electrons and neutrons in 7 (a) Balance this equation (b) Water is formed in this reaction. Draw a diagram to show how the outer electrons are shared in a molecule of water. Exercise 9 Substance Melting point Electrical conductivity Solid Solution Melt W High Non-conductor Non-conductor Non-conductor X High Conductor Insoluble Conductor Y Low Non-conductor Non-conductor Non-conductor Z High Non-conductor Conductor Conductor (a) Using the information in the table, state whether W,X,Y and Z are simple covalent, network covalent, ionic or metallic. (b) Explain why Z cannot conduct in the solid state, but becomes a good conductor when molten.. (a) State what is meant by electrolysis. 7

8 (b) Aluminium is extracted by electrolysis of its molten oxide since aluminium oxide does not react when heated with carbon. Why does aluminium oxide not react with carbon? (c) Chlorine is produced by the electrolysis of sodium chloride solution. Write the ion-electron equation for the formation of chlorine. You may wish to use the data booklet to help you. Ammonia gas can be produced in the lab by heating ammonium chloride with sodium hydroxide. Calculate the mass of ammonia produced by heating 0kg of NH Cl NH Cl + NaOH NaCl + H O + NH Exercise 0 (ii) Calculate the number of moles of sodium hydroxide in this average volume. Show your working clearly. (b) mole of ethanoic acid reacts with mole of sodium hydroxide. Calculate the concentration in mol/l of ethanoic acid in vinegar. Show your working clearly. 5. Iodine can react with propene in the following way: 8

9 (a) (i) Name the homologous series to which propene belongs. (ii) Name the type of chemical reaction which takes place when iodine reacts with propene. (b) Calculate the mass of iodine that will react with 00g of propene.. Which of the following metals would react with zinc chloride solution (use page 7 of the data booklet) A Copper B Gold C Iron D Magnesium Exercise Metal salts can be made by using different methods. (a) Barium sulphate can be made by reacting solutions of barium chloride and sodium sulphate. The ionic equation for this reaction is: Ba + (aq) + Cl - (aq) + Na + (aq) +SO - (aq) Ba + SO - (s) + Na + (aq) + Cl - (aq) (i) Rewrite the equation omitting spectator ions. (ii) Name the type of reaction taking place. (b) Potassium sulphate can be made by titrating sulphuric acid with potassium hydroxide solution. KOH (aq) + H SO (aq) K SO (aq) + H O (l) If 5cm of dilute sulphuric acid were required to react with 0cm of 0.mol/l potassium hydroxide solution, calculate the concentration of the sulphuric acid. () Identify the type of bonding that is likely to be present in the following: (A) Mercury (B) Silver (I) chloride (C) Carbon monoxide (D) Silicon oxide (). A SO B CuO C Na O D NO (a) Which letters show compounds which will dissolve in water to produce acidic solutions? 9

10 (b) Which letter shows a compound which will dissolve in water to produce an alkaline solution? (c) Which letter shows a compound which will form a neutral solution? () Calculations Exercise Ammonia gas can be produced in the lab by heating ammonium chloride with sodium hydroxide. Calculate the mass of ammonia produced by heating 0kg of ammonium chloride NH Cl + NaOH NaCl + H O + NH. Zinc sulphide, roasted in air, reacts as follows: ZnS + O ZnO + SO (a)calculate the mass of sulphur dioxide produced when 9.7g of zinc sulphide is completely roasted in air. (b) Suggest why this process could damage the environment.. (a) Calculate the volume of 5moles of a 0.5 mol/l solution of HCl(aq). (a) Write chemical formula for sodium hydroxide. (b) Calculate the volume of moles of mol/l sodium hydroxide. 5. Potassium sulphate can be made by titrating sulphuric acid with potassium hydroxide solution. KOH (aq) + H SO (aq) K SO (aq) + H O (l) If 5cm of dilute sulphuric acid were required to react with 0cm of 0.mol/l potassium hydroxide solution, calculate the concentration of the sulphuric acid. Exercise Copy and complete the following word equations & write the chemical equation underneath. (a) Sodium hydroxide + Nitric acid (b) Lithium hydroxide+hydrochloric acid (c) Sodium oxide + Hydrochloric acid (d) Calcium oxide + Nitric acid (e) Calcium carbonate + Nitric acid 0

11 (f) Copper (II) carbonate+hydrochloric acid. Complete the following equations and circle the precipitate. (a) Lead nitrate + Magnesium sulphate (b) Magnesium nitrate + Sodium hydroxide (c) Zinc sulphate + sodium carbonate (i) Write chemical equations for the reactions above, showing ionic charges, and circle the spectator ions. Exercise (a) State the colour change when a sugar reacts with benedict s solution. (b) Which sugar does not react with benedict s? (c) State the test for starch. (d) Glucose and fructose both have the formula C 6 H O 6 but they have different structures. What name is given to such compounds which have the same formula but different structure?. A Na O B ZnO C SnO D PbO E CuO F Hg O (a) Which oxide could be broken down by heat alone? (b) i.which oxide could not be broken down by heating with carbon? ii. What process would have to be carried out on this oxide, to extract the metal? A Silicon Dioxide B Carbon Dioxide C Sodium Oxide D Iron Oxide E Sulphur Dioxide F Copper Oxide (a) Identify which oxides contain transition metals (b) Identify the oxide which reacts with water in the atmosphere to make acid rain (c) Identify the oxide which, when added to water, produces a solution with a greater concentration of hydroxide(oh - ) ions than hydrogen ions (H + ).. Draw full structural formula for the following:

12 (a) pentane (b) Cyclohexane (c) ethene (d) but--ene. Exercise 5 The grid shows some statements which could be applied to a solution A It does not react with magnesium B It has a ph less than 7 C D E It does not conduct electricity It produces chlorine gas when electrolysed It contains more H + ions than pure water Identify the two statements which are true for both dilute hydrochloric acid and dilute sulphuric acid.. The table contains information about some substances Substance Melting point/ o C Boiling point/ o C Conducts as solid Conducts as a liquid A No No B Yes Yes C Yes Yes D No Yes E No No F No No (a) Identify the substance which is a gas at O 0 C (b) Identify the two substances that exist as molecules (c) Identify the covalent network substance (d) Identify the ionic substance. David was studying the reactions of some metals and their compounds. He carried out experiments involving magnesium, copper, zinc, nickel, silver and unknown metal X Listed below are some of his observations A X was more easily oxidised than copper B X oxide was more stable to heat than silver oxide C Magnesium displaced X from a solution of X nitrate D X reacted more vigorously than nickel, with dilute acid E Compounds of X were more readily reduced than compounds of zinc David produced the following order of reactivity MOST Magnesium > Zinc > Nickel > Copper > X > Silver LEAST REACTIVE REACTIVE

13 Identify the two observations which can be used to show that X has been wrongly placed.. Calculate the percentage, by mass, of calcium in fluorite(caf ) Showing your working clearly 5. Iron can be extracted by heating haematite (Fe O ) with carbon monoxide. Carbon dioxide is also produced in the reaction. Write an equation, using symbols and formulae, for this reaction Exercise 6 The grid shows some ionic compounds A Aluminium Bromide B Sodium Chloride C Potassium Hydroxide D Sodium Sulphate E Potassium Bromide F Calcium Chloride (a) Identify the base (b) Identify the two compounds whose solutions would form a precipitate when mixed (c) Identify the compound with a formula of the type XY, where X is a metal.. (a) Which pair of metals would produce a flow of electrons in the same direction as shown in the diagram and produce a blue colour round metal B? (b) Which pair of metals would produce the biggest voltage? (Page 7 data book).

14 Siobhan carried out some experiments with metals (W, X, Y and Z) and some of their compounds. She made the following observations: (a) Name the gas formed when metal Y reacts with water. (b) Suggest names for metals W and Y. (c) Place the metals in order or reactivity (most reactive first) (d) Name the type of chemical reaction which takes place when a metal is extracted from its oxide. Exercise 7 (a) Calculate the formula mass of sodium carbonate (b) Calculate the mass of solute (sodium carbonate ) present in 00cm of sodium hydroxide solution, concentration 0.mol/l 5 (c) Mg + H SO MgSO + H Use the above equation to calculate the mass of hydrogen released when g of Mg is added to excess sulphuric acid.. Dienes are a homologous series of hydrocarbons which contain double bonds per molecule. (a) What is meant by the term homologous series? (b) Suggest a general formula for the dienes. (CnH? ) (c) Write the full structural formula for the product of the complete reaction of penta-,-diene with bromine.. Reactions can be represented using chemical equations A B C D Fe + (aq) + e - Fe (s) Fe + (aq) Fe + (aq) + e H (g) + O (g) H O (g) H O (l) +O (g) + e - OH - (aq)

15 E SO (g) + H O (l) H + (aq) + SO - (aq) (a) Identify the equation which shows the formation of acid rain (b) Identify the equation which represents a combustion reaction (c) Identify the two equations which are involved in the corrosion of iron Exercise 8 When superglue sets, a polymer is formed. The polymer has the following structure. (a) Draw the structural formula for the repeating unit. (b) Draw the structural formula for the monomer in superglue. Q continued (c) Name a toxic gas given off when superglue burns. (d) As the polymer forms, it releases large amounts of heat. What name is given to this type of reaction?.. 5

16 (i) (ii) Which of the following compounds dissolves in water to give a solution with a ph greater than 7? A Ammonia B Carbon Dioxide C Sulphur Dioxide D Sodium chloride (iii)draw a section of the polymer formed when propene monomers combine Exercise 9 (a) Ethene can be used to make poly (ethene). Draw the structure of the polymer showing three ethene units joined together. (b) Poly (ethene) is a thermoplastic. Explain the meaning of the term thermoplastic. (c) Poly(ethene) can t be described as biodegradable. What does biodegradable mean? (d) Name a biodegradable polymer (e) What is the raw material used to make all synthetic plastics? 5. A Nitrogen B Oxygen C Water D Carbon Dioxide E Methane F Ethanol (a) Identify the substances used by plants during photosynthesis (b) Identify the two substances produced during fermentation of glucose solution (c) Identify the substances produced during respiration in humans (d) The substance used up in the combustion of starch. A Nitrogen Dioxide B Hydrogen D Carbon Dioxide E Ammonia C Oxygen F Nitrogen Identify (a) The two gases used as reactants in the Haber Process (b) The two gases used as reactants in the Ostwald Process (c) The gas that is produced during lightning storms and near spark plugs in car engines (d) The gas that makes up 80% of the air (e) The gas that dissolves to give an alkaline solution 6 6

17 (f) The gas that is produced by the Haber Process 7