- Solutions 16

Write the empirical formula corresponding to the following molecular formula: (a) Al_{2}Br_{6}

Okay guys, so in this question they want us to write the empirical formula based on the molecular formula that they give us.

First let's find the difference between the molecular formula and the empirical formula. The molecular formula is going to be the actual formula that is there. So molecular is going to be your actual. Now the empirical formula is going to be your simplest possible formula. So it has to be your simplest whole number ratios of the most, in your formula. So here our formula is going to be Al2Br6. This is our molecular formula and they want us to write the empirical formula. So we have to simplify the ratios as much as possible. So we have two and we have six. All we have to do is, since they're both even, is to divide both moles by two so we could simplify this to AlBr3. Alright, because two divided by two is one and six divided by two give us three and this is the lowest ratio that we have with whole numbers, so we cannot divide by anything else, or we cannot simplify it more, which will give us fractions or decimals.

Alright guys, so once again, when we're doing the empirical formula we have to find the lowest whole number ratio possible. Alright, let's move on.