## Percent by mass:

A student has 7.32 g of copper chloride in a beaker. It takes him 11.2 mL of water to completely dissolve all the salt. Calculate the concentration as percent by mass.

## Percent error:

The solubility of copper chloride a 25°C is 75.7 g/ 100 mL. The student assumes that he has now a concentrated copper chloride solution. Is he correct? Calculate the percent error.

## Sample calculations:

## Molar mass:

1. Identify the elements present in the compound.

2. Multiply the molar mass of each element by the subscript attached to the element in the chemical formula.

3. Add the results from step 2. This is the molar mass of the compound.

Remember to always write grams/mole.

How much NaCl do you need to weigh to make 1 L of a 1

2. Multiply the molar mass of each element by the subscript attached to the element in the chemical formula.

3. Add the results from step 2. This is the molar mass of the compound.

Remember to always write grams/mole.

How much NaCl do you need to weigh to make 1 L of a 1

*M*sodium chloride solution?## Molarity

M = moles of solute/liters of solution

A student uses 5.00g of NaCl to make 1L of solution. What is the molarity of the solution?

A student uses 5.00g of NaCl to make 1L of solution. What is the molarity of the solution?