Explain the steps you would follow to make 500 mL of a 0.3 M solution of sucrose (C12H22011) in the lab.

see explanation

Explanation:

Solutions are prepared from one of three solute sources ...

- solid solute from manufacturer,

-liquid solute from manufacturer,

-stock concentrate of solute for dilution to lower concentrations.

In this problem, sucrose is a stock solid with a formula mass of 342.3 grams/mol. The amount of solid needed can be determined using the formula:

mass of solute needed (grams) = (Molarity needed x Volume needed in Liters x formula weight) / (decimal fraction purity of stock solid)

Molarity needed = 0.3M

Volume needed = 500 ml = 0.500 liters

Formula weight = 342.3 grams/mole

Purity factor (assumed) = 100% = 1.00 (should be posted on stock bottle label) For example, a 95% pure stock solid => purity factor of 0.95.

∴ grams of sucrose needed = (0.3M*)(0.500L)(342.3g/mole)/(1.00) =51.345 grams sucrose.

Measure 51.345 grams of sucrose into mixing vessel and add solvent water up to, but not to exceed 500 ml total volume. Mix until homogeneous.