Determine the amount of water of crystallization of sodium carbonate from a bottle containing anhydrous sodium carbonate which was left uncovered and labeled T1. Sodium carbonate (Na2CO3) coded T1 with unknown concentration; solution T2 containing 3.65 g of hydrochloric acid (HCl) in 1 dm3 and MO methyl orange indicator. Measure 10 cm3 of T1 and dilute it with distilled water up to 150 cm3 in a volumetric flask. Transfer the resulting solution into a beaker provided then pipette 20.00 cm3 (or 25.00 cm3) of the obtained solution and then transfer the pipetted solution into a conical flask. Procedures: Titrate T2 (from the burette), against T1 (in the titration flask) using MO until the end point. Record the results including one rough and three accurate titrations in a tabular form.

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Students were debating about the heat of reaction when dissolving anhydrous copper(II) sulphate and hydrated sodium thiosulphate in water. The argument was whether such reaction releases or absorbs heat. You are consulted to help to find the correct answer for their debate. In the process of undertaking the task, you are required to use the following: R1: Anhydrous copper (II) sulphate (CuSO₄); R2: Hydrated sodium thiosulphate (Na₂S₂O₃.5H₂O); Distilled water, thermometer, plastic beaker (100 cm³), 100 cm³ measuring cylinder and a stopwatch. Perform the experiment through the activities in the procedure and then answer the questions that follow. Procedure (i) Measure 50 cm³ of distilled water and transfer it in the plastic beaker. Record the initial temperature in degree centigrade as T initial. (ii) Weigh 4.0 g of R1 and transfer the salt into the measured water in (i) and immediately start a stopwatch while stirring gently the mixture with a thermometer. (iii) Record the temperature in every 1-minute time interval five times. (iv) Clean and dry the beaker ready for the second experiment. (v) Repeat step (i) to (iii) except that instead of 4.0 g of R1 in step (ii), use 6.0 g of R2. (vi) Record temperature in 1-minute time interval five times.

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The sample salt was brought to your college as sample R. Perform a systematic qualitative analysis experiment to identify the cation and the anion present in the sample. Base your experiment on the listed tests and then answer the questions that follow: (i) Appearance of sample R (ii) Action of heat on sample R in a test tube (iii) Action of dilute sulphuric acid on the solid sample (iv) Action of concentrated sulphuric acid on solid sample (v) Flame test (vi) Solubility of the sample (vii) Confirmatory test for the anion (viii) Confirmatory test for the cation

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