RESOURCEFUL EXAMINATIONS UGANDA ADVANCED CERTIFICATE OF EDUCATION CHEMISTRY PAPER2.pdf

1 Candidate’s Name: ………………………………………………………………………………………… P525/2 CHEMISTRY Paper 2 Jun-Jul. 2026 3 1/4 hours Resourceful examination Uganda Advanced Certificate of Education CHEMISTRY Paper 2 3 hours : 15 minutes INSTRUCTIONS TO STUDENT S:  This paper contains two compulsory items, 1 and 2. You must answer both.  Write your answers in the spaces provided in this booklet, using either blue or black ink. Show all working clearly.  You may use mathematical tables and a silent, non - programmable scientific calculator.  Reference books such as textbooks or booklets on qualitative analysis are not allowed.  Read each item carefully before starti ng. Make sure you have all the apparatus you need, and plan your work appropriately. For scorers’ use only CODE Scores CODE Scores A A H H V V P P R/M R/M Dp Dp Di/a Di/a C/R C/R Total TOTAL Turn over Page2 ITEM 1. At the Uganda Industrial Research Institute (UIRI) in Nakawa, a team of researchers is developing a new water treatment process that utilizes potassium manganate(VII) ; (KMnO₄) to remove iron and manganese impurities from groundwater sources in rural Uganda . To ensure the effectiveness of the treatment process, the tea m needs to standardize the potassium manganate(VII) solution using a primary standard; hydrated ammonium ferrous sulphate ; ((NH₄)₂SO₄·FeSO₄·6H₂O) available in the laboratory . Additionally, they want to use the standardized potassium manganate(VII) to determine the molecular mass of an unknown oxalate compound, X₂C₂ O₄, which is used as a scale inhibitor in industrial boilers. The technician recommended using a redox titrati on between hot acidif ied oxalate solution at 60°C (acidified with equal volume of sulphuric acid) with manganate(VII) solution. He further mentioned that the exact concentration of is between 0.018 to 0.022 and that molecular of t he oxalate salt lies between …