To determine the % by mass of manganese (IV) oxide in a solid sample. ( By Titration )

Procedure: 1. on the whole instruments were cleanseed by using deionised water. 2. 25cm3 of sodium thiosulphate antecedent was pipetted give away and pour into a volumetric flaskful. 3. Deionised water was added to the first mark. Part A 1. thin sodium thiosulphate radical with unvalued concentration was poured into the burette. 2. 25cm3 of monetary standard 0.027M iodine settlement was pipetted aside and pour into a conical flask. 3. The iodine resultant was titrated with sodium thiosulphate solution until it became pale jaundiced in colour. 4. Few drops of stiffen as indicator were added to the solution. 5. Titration was sinless when the colour of the solution changed from down in the mouth to colourless. 6. Further 2 close titrations were performed. Part B 1. All instruments were washed by using deionised water. 2. 1g of the solid manganese(?) oxide was leaden and drop into a conical flask. 3. 25cm3 of 1M potassium iodide was pipetted out and fuse with th e solid. 4. 20cm3 of 12M toilsome hydrochloric venomous was measured by measuring cylinder. 5. The concentrated hydrochloric acid was mixed with the solid. 6. 25cm3 of 1M potassium iodide was pipetted out and mixed with the solid. 7. The solution was excited gently. 8. The solution was poured into a 250cm3 volumetric flask. 9. The conical flask was washed with small quantities of water. 10.

All washes were poured into the 250cm3 volumetric flask. 11. No solution was sacrifice on the wall of the flask. 12. Water was added with a wash nursing bottle until the graduation mark and then shook well. 13. Diluted sodiu m thiosulphate solution (standardized in Par! t A) was poured into the burette. 14. 25cm3 of the diluted solution was pipetted out and poured into a conical flask. 15. The diluted solution was titrated with diluted sodium thiosulphate solution until a pale yellow... If you want to take in a full essay, order it on our website: BestEssayCheap.com

If you want to get a full essay, visit our page: cheap essay