Answer: [tex]KCrO_4[/tex]
Explanation:
First, calculate how much percent of oxygen there is. We know that the whole compound cannot exceed 100%, so we take that, and substract it from 26.56% and 35.41%.
100.00
- 26.56
-------------------
73.44
- 35.41
---------------------
38.03
That is how much of oxygen we have.
Potassium: 26.56% or 26.56g
Chromium: 35.41% or 35.41g
Oxygen: 38.03% or 38.03g
To find the empirical formula, you simply find the amount of mol that each one has. You can do this by using the atomic mass of each element.
[tex]Potassium: 26.56g(\frac{1mol}{39.10g})= 0.67mol[/tex]
[tex]Chromium: 35.41g(\frac{1mol}{52g})=0.68mol[/tex]
[tex]Oxygen: 38.03g(\frac{1mol}{16g})=2.38mol[/tex]
We now determine the lowest number and divide each mol by it. In this case, the lowest number is 0.67
[tex]Potassium: \frac{0.67mol}{0.67}=1[/tex]
[tex]Chromium:\frac{0.68mol}{0.67}=1[/tex]
[tex]Oxygen:\frac{2.38mol}{0.67}=3.55 = 4[/tex]
Finally, we take each element add add their respective number.
So, this empirical formula would be:
[tex]KCrO_4[/tex]
