Hey Bobby how have you been doing? Are you still playing football?
Hey Linda! I'm doing ok and yes I still play football but its been hard to keep my helmet from rusting.
Oh no that sucks! Rust gets on my nerves. The other day I was walking down my metal steps and it cut me because it was rusty.
But what even is Rust?
Well technically speaking, rust is 69.94% Iron and 30.06% Oxygen.
What the....How'd you know that ?
Woah ... Can you show me how?
It's pretty easy actually,I just found out the percent composition of Iron and Oxygen Which are 2 elements that make up rust or Fe203!
Of course Linda!
The formula for percent composition of each element is (element mass)/(total Compound Mass)*100
So first off remember that percent composition is the percentage by mass of each element in a compound, in simple terms OIts substance is in the overall substance.
To find the mass of a element ,all u got to do is go to the periodic table. Take the atomic mass listed for that element and multiply it by the number of atoms of the element in the compound. So if its Rust (Fe2o3), Iron(Fe)´s mass is 55.845. Multiply that by 2 since there are 2 atoms of Fe and you get 111.69
To get the total compound mass, you add together all the elements masses thatthat make up the compund. So in in the case of Rust ,we already got the mass of Iron which is 111.69. Oxygen atomic mass is 15.999, Multiply that by 3 since there are 3 atoms of it in Fe203 and get 47.997. Add 111.69+47.997 and get 159.687.
So that's how much Iron is in Rust on your Football helmet! THanks for the lesson! IT was good to see you Bobby
No problem Linda
Lastly, you divide the specific element by the total mass and times it by 100 and there's your percentage! So for iron in rust divide 111.69 by 159.687 and multiply that by 100 and you get 69.94%!