Unit 2 Assignment A

Assignment 2A
Part 1: Preparation of a standard solution
Risk Assessment:

Hazard Risk Control Measure
Sodium Carbonate It’s an irritant Wash the skin if it touches
immediately
Liquid Slip over Clean up any spillages straight
away
Glassware Cut open skin Clean up any broken glass
Method

1. Calibrate the weighing balance that you will be using
2. Weigh approximately between 1.25g and 1.45g of anhydrous sodium carbonate on a
weighing boat. Make sure none of the sodium carbonate goes outside the weighing boat.
3. Carefully transfer the sodium carbonate to a 250 cm3 beaker, accurately and precisely
recording measurements to determine the exact mass transferred
4. Add 150cm3 of distilled water to the beaker, stir and completely dissolve the sodium
carbonate
5. Carefully and accurately transfer all of the solution to a 250 cm3 volumetric flask, and make
up the solution to 250cm 3 with more distilled water

Calibration’ Reading on Reading on Reading on Average
mass/ Actual balance balance balance
mass
1 2 3
1.00g 1.00g 1.00g 1.00g 1.00g
2.00g 2.01g 2.00g 2.00g 2.00g
5.00g 5.00g 5.00g 5.00g 5.00g
20.00g 20.05g 20.01g 20.01g 20.02g


Mass of sodium carbonate = 1.35g

Volume of water = 250ml

1.35/106 = 0.013 (This is the moles of sodium carbonate)

0.013/0.25 = 0.052 mol /dm3

Part 2: Standardisation of an acid
Risk Assessment

Hazard Risk Control Measure
Glass Can cut the skin Clear up any broken glass
Sodium Carbonate It is an irritant Wash the skin immediately if it
comes into contact
Method