Question

3. Many metal ions are toxic, so adding a compound to force the metal ions to precipitate as an insoluble compound before filtering is an effective method of removing those toxic ions from the solution. When choosing a precipitating agent, like the sodium hydroxide used in your experiment or the sodium carbonate used above, a chemist has to take a variety of chemical, environmental, and economic factors into consideration. What do you think some of those might be? Name three such factors you would investigate before choosing the best reagent.

Answer 1

Solution:

The important considerations for choosing a precipitating agents are:

1) The precipitating agents must have low solubility.

2) It can be easily filtered and prone to less contamination.

A crystaline agent posses less contamination than noncrystaline precipitating agent.

3) The precipitating agent is unreactive to atmospheric gases like O2, N2, H2 etc.