For example, to make 100 ml of 0.1 M CaCl2 solution, use the previous formula to find out how much CaCl2 you need:
grams of CaCl2 = (0.1) x (110.91) x (100) ÷ (1000) = 1.11 g
Now you can make your solution: dissolve 1.11 g of CaCl2 in sufficient water to make 100 ml of solution. The amount of water needed will be slightly less than 100 ml.
A balance and a volumetric flask are used to make molar solutions. A procedure for making a molar solution with a 100 ml volumetric flask is as follows:
Calculate the weight of solute needed to make 100ml of solution using the above formula.
Weigh out amount of solute needed using a balance.
Transfer the solute to a clean, dry 100ml volumetric flask.
Add distilled water slowly to the volumetric flask. Wash all the solute into the bottom of the flask as you do so. Keep adding water until you reach the 100ml mark on the neck of the flask.
Place the stopper in the flask and gently swirl the flask until all the solute is dissolved.
If you don’t have a volumetric flask you can use a 100ml graduated cylinder instead. Just add the solute to the graduated cylinder and then add distilled water until you reach the 100ml mark in the side of the cylinder.
How to Make Weight Percent (Wt%) Solutions
In weight percent solutions, the weight of the solute is divided by the weight of the solution (solute + water) and multiplied by 100. Since the density of water is 1 g/ml, the formula to calculate the amount of solute that must be mixed for a weight percent solution is:
grams of solute = (wt% solution) x (ml of water) ÷ (100 – wt% solution)
As an example, to make 100 ml of 10% NaCl (table salt) solution, use the previous formula to find out how much NaCl you need:
grams of NaCl = (10) x (100) ÷ (100 – 10) = 11.1 g
Now you can make your solution: dissolve 11.1 g NaCl in 100 ml of water.
Step-by-step explanation:
this should be more helpfull sorry bout yesterday
