Propane (C3H8) has a molar mass of 132 g/mole. You started out the day with a tank containing 9071 g of propane. At the end of the day, your tank contained 7532 g of propane gas. How many moles of gas did you use?

To solve this, first consider how many grams of propane you lost during the day. This can be seen by subtracting 9071 g by 7532 g. This gives a value of 1539 g. To get moles from this, remember that molar mass, 132, is in grams per mole. We have 1539 g of propane used, so to find this is mole, we can divide it by the molar mass 132 grams per mole.

1539 grams x 1 moles/132 grams

In this way, we can cancel out grams and be left with moles.

Answer:

11.66 moles of propane