# Using normality in Chemistry How much AlCl(subscript =3)should be dissolved in a 2.0L solution to produce a .15N solution. Please show steps?

### 1 Answer

- pisgahchemistLv 71 year ago
Normality .....

Normality is an arcane unit of concentration which has just about been relegated to the dustbin of chemistry. It still shows up in some older papers, procedures and books, but modern chemistry textbooks may not even mention it at all. Any references to normality should be updated to molarity.

normality = molarity x number of hydrogen equivalents

For aluminum, that is 3. Therefore, a 0.15N solution has a molarity of 0.050M.

2.0L x (0.050 mol AlCl3 / 1L) x (133.35g AlCl3 / 1 mol AlCl3) = 13.3g AlCl3

Steps? Simply use the unit-factor method. The first conversion factor gives the moles of AlCl3. Liters cancel out. The second conversion factor gives the mass of AlCl3. Moles cancel out. We can use the unit-factor method to solve the vast majority of chemistry problems.