SASS Chem Salts Preparation Summary

PREPARATION OF SALTS : A WALKTHROUGH B 5JUSBUJPO BR41"TBMUT C "#$.NFUIPE BROPO41"TBMUT D 1SFDJQJUBUJPO JOTPMVCMFTPMJET (a) Titration ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ 2 5070/41/O/N/12© UCLES 2012 For Examiner’s Use 1 The following apparatus is found in a laboratory. ABC 25 cm3 100 50 0 10 20 30 40 50 DEF Write the letter of the apparatus most suitable for the purpose in the table below. purpose apparatus (a) removing 25.0 cm3 of a liquid from a container (b) measuring about 60 cm3 of a liquid (c) as a titrating flask (d) to separate a precipitate from a solution [Total: 4] www.maxpapers.com 2 5070/42/M/J/20© UCLES 2020 1 Iron tablets are used to treat iron deficiency in the body. Iron tablets contain iron(II) ions, Fe2+. A student does a series of titrations with aqueous potassium manganate(VII), KMnO4, to determine the percentage of iron in some iron tablets. Diagrams of some of the apparatus the student uses are shown. A B C 25 cm3 10 1 2 3 4 5 6 7 8 9 (a) Name the three pieces of apparatus. A ............................................................................................................................................... B ............................................................................................................................................... C ............................................................................................................................................... [3] (b) The student: • records the total mass of five iron tablets • crushes the tablets, dissolves them in distilled water and makes the solution up to 250 cm3 • uses apparatus C to transfer 25.0 cm3 of the solution of Fe2+ ions into a conical flask • uses apparatus B to add 10.0 cm3 of dilute sulfuric acid to the conical flask • fills apparatus A with 0.00500 mol / dm3 KMnO4(aq) • titrates the solution of Fe2+ with the 0.00500 mol / dm3 KMnO4(aq) until the first permanent pink colour is seen in the conical flask • repeats the titration three times. 6 Do not write outside the box (06) G/K93725/Jun13/CH3HP 3 In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate. A student used the equipment shown to do a titration. Burette White tile Conical flask Acid Pipette Sodium hydroxide Pipette filler Indicator Describe how a student should use this equipment to find the volume of sodium hydroxide solution that reacts with a known volume of acid. Include any measurements the student should make. Do not describe how to do any calculations. ............................................................................................................................................ ............................................................................................................................................ ..........................