How would you prepare 100ml of .400MCaCl2 from a stock solution of 2.00MCaCl2

Use c₁V₁ = c₂V₂. 2.00 M · V₁(CaCl₂) = 0.400 M · 100.0 mL. V₁(CaCl₂) = (0.400 M · 100.0 mL) ÷ 2.00 M. V₁(CaCl₂) = 20 ml.

Explanation:

14 days is the half-life of phosphorus-32

water and alcohols have similar properties because water molecules contain hydroxyl groups that can form hydrogen bonds with other water molecules and with alcohol molecules, and likewise alcohol molecules can form hydrogen bonds with other alcohol molecules as well as with water.