A Reaction Between Sodium Phosphate and Calcium Chloride
The purpose of this lab is to determine the theoretical yield and the percent yield of a reaction between
aqueous sodium phosphate and aqueous calcium chloride.
- You will need 3 beakers and a stirring rod.� Make sure they are all clean and have been rinsed with distilled water before using them.
- Measure out 0.9-1.1 g of anhydrous CaCl2 and place it in your smallest beaker (50 ml or 100 ml).� Add 20.0 ml of distilled water and dissolve using a clean glass stirring rod.
- Measure out 1.9-2.1 g of Na3PO4.12 H2O (hydrated sodium phosphate) and place it in a clean 100 ml or 150 ml beaker.� Add 40.0 ml of distilled water and dissolve using a clean glass stirring rod.� Note:� The sodium phosphate solid you are using is not anhydrous.� It is a hydrate1, meaning that it has water molecules trapped inside of its crystal lattice structure.� In fact, every gram of the solid that you measure out only contains 0.43 g of Na3PO4.
- Add the aqueous calcium chloride to the beaker containing aqueous sodium phosphate.
- Write your initials on a piece of filter paper and determine its mass.� Fold the filter paper to make it fluted and use it to filter out all of the solid precipitate that you obtained in step 4.� Use your wash bottle (distilled water) to rinse out the beaker to capture as much of the product as possible.
- When you have collected as much of the filtrate2 as possible, place the filter paper in a drying oven overnight and determine the mass of your precipitate the next day or thereafter.
1 Many ionic solids absorb moisture from the air forming hydrates.
2 The filtrate is the liquid that passes through the filter paper.