Topic C6 Chemical Synthesis Homework booklet Graph paper required for homework two Name Key terms and spellings on back page Due Date Teacher Comment Homework 1 Homework 2 Homework 3 Homework 4
Homework One: Chemical Curiosities: Surprising Science and Dramatic Demonstrations Enjoy watching this film of great chemistry experiments on You Tube. You can search You Tube for the title above or use the qr code or url. Write a very short report (no more than 3 sentences) in the box below http://goo.gl/vtgmj1 My favourite demonstration/reaction Homework Two: Rates of Reaction What can you do to speed up a chemical reaction? Colour in or shade the boxes that would work increased concentration of dissolved reactant increased concentration of dissolved product increased pressure of gaseous reactants increased surface area of solid catalyst increased temperature of reactants add a catalyst and increase the concentration of the reactants demand the chemicals react faster or else. giving the reaction verbal encouragement increased surface area of solid reactant greater volume of reacting solution use freshly made up solutions use more concentrated reactants smaller particles (lumps) of solid larger surface area and a higher increased surface area of solid reactant reactant temperature presence of suitable enzyme increase concentration of dissolved catalyst increase size of reaction vessel stir well add a catalyst stare at the reaction in a menacing fashion use a powder instead of a lump buy more expensive chemicals carry out the experiment at a higher temperature shake write to your MP and demand action Calcium carbonate reacts with hydrochloric acid to make carbon dioxide, calcium chloride and water. Here are the results of an experiment carried out at 20 o C where 40cm 3 of dilute hydrochloric acid were poured onto a marble (calcium carbonate) lump. Time (min) Mass of flask and contents (g) 0 1 2 3 4 5 6 7 8 9 71.00 70.74 70.54 70.40 70.30 70.24 70.26 70.20 70.20 70.20
1. Explain why the mass drops 2. Plot the data on a graph and draw a line of best fit. 3. Circle the unreliable result 4. Mark a F on your graph to show where the reaction is fastest 5. Mark an X on your graph to show where the reaction stops. 6. Give three things that you could do to increase the rate of the reaction? a. b. c. 7. Add a line to your graph to show what it would look like if the same experiment was done at a higher temperature Homework Three: Titrations 1. Add two labels to the diagram 2. What volume of liquid is in the burette? 3. What piece of equipment is used to put the liquid in the conical flask 4. In a titration experiment Josh put 20.00cm 3 of 1.30 mol/dm 3 hydrochloric acid into the conical flask. He neutralised the acid by adding sodium hydroxide from the burette. Here are his results: Titration one Titration two Start volume 0.00 cm 3 Start volume 16.20 cm 3 Final volume 16.20 cm 3 Final volume 32.30 cm 3 Titre Titre Now use the equation that follows to complete the table Concentration of sample = concentration of standard x titre of standard titre of sample show your working here Mean titre cm 3 Mean concentration mol/dm 3
Homework Four Look back over your work or use a revision book to answer all these questions. 1 What word describes a reaction that absorbs energy? 2 What is a catalyst? 3 Give the ph range of acids 4 What hazard warning symbol should you find on a bottle of concentrated acid? 5 Give three things you could do to slow down the rate of a chemical reaction 6 Name two solid acids 1 2 3 7 Name a gaseous acid 8 Name two indicators 9 What ions do all acids contain 10 Give the formula of the ion found in alkalis 11 What piece of equipment is used to dry a chemical produced in a lab? 12 Name the two main pieces of glassware used to carry out a titration 13 Draw a diagram based on collision theory to show why concentrated acids react more quickly with metals than dilute acids 1 2 14 Give the formula of calcium carbonate 15 Give the formula of calcium sulphate 16 Write an equation to represent the reaction between sulphuric acid (H 2 SO 4 ) and sodium hydroxide 17 Write an equation to show the reaction between magnesium and hydrochloric acid 18 What are the three products of the reaction between zinc carbonate and nitric acid 19 In a titration, 21.00cm 3 of 1.00mol/dm 3 sodium hydroxide neutralised 42. 00cm 3 of hydrochloric acid. What is the concentration of the acid? 1 2 3
20 Name the salt produced in the Q19 titration 21 What piece of equipment (not indicator) can be used to measure ph? 22 What word describes a reaction that releases heat energy? 23 The theoretical yield of a chemical is 6.2g. Leo obtained 5.8g. Calculate the yield 24 Give one reason that it can be dangerous if the rate of a chemical reaction if very high Identify three factors that affect the rate of reaction of magnesium with hydrochloric acid, and describe the effect of each of these factors on the rate of the reaction. Choose two of the factors you have identified. Use ideas about collision theory to explain why these factors affect the rate of the reaction in the ways that they do. The quality of written communication will be assessed in your answer to this question. [6]
Key terms and spellings acid alkali burette catalyst carbonate citric acid collision theory corrosive concentration crystallisation endothermic ethanoic acid exothermic desiccator filtration hazard symbol hydrogen ion (H + ) hydroxide hydroxide ion (OH - ) indicator litmus paper neutralisation oxidising particle size ph pharmaceuticals ph meter pipette purification quantitative rate of chemical reaction reactants reacting masses reaction rate relative atomic mass relative formula mass salt state symbol synthesis tartaric acid temperature titration universal indicator yield