# Question #a1072

##### 1 Answer

A mole ratio is used to convert the number of moles of one substance to number of moles of another substance.

A mole ratio is a fraction made up from the coefficients in a balanced equation.

For example, in the equation

6 Li(s) + N₂(g) → 2 Li₃N(s)

We could have the following mole ratios:

EXAMPLE 1:

What is the mole ratio between Li and N₂ in the reaction?

6 Li(s) + N₂(g) → 2 Li₃N(s)

Answer:

We pick the fraction that gives us the correct units in a particular problem.

EXAMPLE 2:

Use the above equation to determine the number of moles of Li₃N that can be prepared using 0.24 mol Li.

Solution

The mole ratio is either

We choose the one that makes the units cancel and gives the correct units for the answer — the second one.

0.24 mol Li ×

Detailed explanation and good video here: http://study.com/academy/lesson/mole-to-mole-ratios-and-calculations-of-a-chemical-equation.html