1. Isotonic saline requires a concentration of 0.85% NaCl. How much solid NaCl must be weighed out on the balance to prepare a bottle full containing 3500 ml?

Given :

Concentration of NaCl , .

To Find :

Th amount of solid NaCl must be weighed out on the balance to prepare a bottle full containing 3500 ml .

Solution :

Concentration of NaCl is 0.85 % .

It means , 0.85 gm of NaCl in 100 ml of water .

So , amount of solid NaCl required to prepare 3500 ml solution is :

Therefore , amount of solid NaCl required is 29.75 gm .

Hence , this is the required solution .

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