Aprescription calls for the following: sodium citrate 5 g tartar emetic 0.015 g cherry syrup ad 120 ml using a balance with a sensitivity of 4 mg, an acceptable weighing error of 5% and cherry syrup as the solvent for tartar emetic, how could you obtain the correct quantity of tartar emetic to fill the prescription?

measure the volume of cherry syrup solution with Tartar Emetic = 22.5 mL

Hence, the correct quantity of tartar emetic to fill the prescription will be obtained

Step-by-step explanation:

Given:

Mass of Sodium citrate = 5 g

Mass of Tartar Emetic = 0.015 g = 15 mg

Volume of Cherry syrup ad 120 mL = 120 mL

sensitivity = 4 mg

Error = 5%

Now,

The smallest weight that can be measured =

or

The smallest weight that can be measured =    = 80 mg

Now,

80 mg is dissolved in 120 mL of Cherry syrup according to prescription

( Thus,

1 mg is dissolved in  of Cherry syrup according to prescription )

so to measure 15 mg of Tartar Emetic, measure the volume of cherry syrup

=  

= 22.5 mL

Hence, the correct quantity of tartar emetic to fill the prescription will be obtained