Calculations (step by step) for unit 19 learning outcome A - Analyte determination

Attached are step-by-step calculations with equations, ratios, units etc which were created for the new unit 19 in the level 3 applied science course (new from 2016). The calculations are for the determination of bicarbonate in bottled water, the amount of copper in brass and the amount of iron in iron tablets.
There are 3 stages to the bottled water practical, the end answer states the concentration of bicarbonate in water (tap water was used to save money!) in moles per decimetre cubed.