Question

Given the following equation, what is the correct form of the conversion factor needed to convert the number of moles O2 to the number of moles of Fe reacted?

4Fe + 3O2 --> 2Fe2O3

4 mol Fe
3 mol O2


2 mol Fe2O3
4 mol Fe


4 mol Fe
2 mol Fe2O3


3 mol O2
2 mol Fe2O3

Answer 1

The correct answer is the first option: 4 mol Fe , 3 mol O2

Step-by-step explanation:

Hello!

Let's solve this!

The reaction is:

4Fe + 3O2 ---> 2Fe2O3

This reads that every 4 moles of iron consumed, we need 3 moles of oxygen and when they react, we get 2 moles of Fe2O3.

Let's analyze each of the options:

4 mol Fe

3 mol O2: this is correct since it tells us how much iron and how much oxygen we need.

2 mol Fe2O3

4 mol Fe: it is not correct because it does not tell us anything about oxygen.

4 mol Fe

2 mol Fe2O3: it is not correct because it does not tell us anything about oxygen.

3 mol O2

2 mol Fe2O3: it is not correct because, although it says of oxygen, it does not relate it to iron.

We conclude that the correct answer is the first option: 4 mol Fe

3 mol O2

Answer 2

Option A says we have 4 moles of Fe for each 3 moles O2

This is correct For 3 moles of O2 consumed, we need 4 moles of Fe to be reacted

Step-by-step explanation:

Step 1: Data given

Step 2: The balanced equation

4Fe + 3O2 → 2Fe2O3

Step 3: Calculate the mol ratio

For 3 moles O2 we'll have 4 moles Fe

Option A says we have 4 moles of Fe for each 3 moles O2

This is correct For 3 moles of O2 consumed, we need 4 moles of Fe to be reacted

Option b says we have 2 mole Fe2O3 for each 4 moles Fe

This doesnt say anything about O2. So doesn't apply for this question.

Option C says we have 4 moles of Fe for each 2 moles Fe2O3

This is the same as option B, so doesn't apply for this question.

Option D says for each 3 moles of O2 we have 2 Fe2O3

This is true, but doesn't say anything about Fe so doesn't apply here.