16. Gravimetric Analysis

What is gravimetric analysis used for?

Calculating mass or concentration of substance by measuring change in mass

What is the aim of gravimetric analysis?

Identification of an unknown metal chloride

What are the safety measures for this experiment?

AgNO3 solution and HNO3 solution are corrosive, HCl solution is an irritant

Why is filtration used?

To remove the solid from liquid

Why is filter paper weight before use?

To measure mass of precipitate accurately -> Mass of filter paper can be taken away at the end

Why should the solution not be allowed to boil?

Ensure no loss of chloride

Why do we carry out multiple washings of metal chloride?

To remove soluble impurities

Why is deionised water used to dissolve the sample?

Tap water contains dissolved ions like chloride which can interfere with the test

Why do we test the wash solution with concentrated HCl?

To ensure there are no Ag+ ions remaining

Why is the final filtrate dried to a constant mass?

To remove all water from the precipitate