Question

How many moles of Fe2O3 are in 235 g of the compound?

Answer 1

Use dimensional analysis approach to cross cancel out terms. First, start by making a plan, that usually helps me out. But before that, write down you're given and what you want.

GIVEN: 235 g of iron III oxide.
WANT: moles of iron III oxide.

You're plan: grams of iron III oxide -> moles of iron III oxide

To find this, find the sum of the molar mass of each element. Remember that you can do this by just adding the amount of each element that you have. Here, you have: 2 Iron, and 3 oxygens. You can find their mass by looking at your periodic table. The units for thier molar mass are: \(\frac{ g }{ mole }\). Now, similar yo how you did in algebra, cross cancel units and you get moles.

Try it, and if you need help or get lost, just ask.