Diluting Solutions

Question

Dichloride of mercury is available as 500 milligram tablets. The tablets are used to prepare 3 liters of a 1:1000 solution.

How many grams of dichloride of mercury are needed?

How many tablets of dichloride of mercury are needed?

Answer 1

The expression 1:1000 means one gram of solute in 1000 grams of solvent. In the case of water as the solvent, 1 gram = 1 milliliter

 

So, for 3 Liters (3000g of water), we will need 3 grams of HgCl₂.

 

The tablets contain 500 milligrams or 0.5 grams.

 

So, we will need 3 grams ÷ 0.5 grams/tablet = 6 tablets.