Chemistry - Atom Economy

[Kardan]

Right, in my GCSE revision book that I bought, I'm told that the equation for Atom Economy is:

(Total Mr of useful products / Total Mr of reactants) x 100

However, during a reivison lesson today, my Chemistry teacher told us the equation for Atom Economy is:

(Total Mr of useful products / Total Mr of products) x 100

Which ones right?

[cocaine]

I ran a few searches on google and every page I found it said

(Total Mr of useful products / Total Mr of reactants) x 100

However you're better off explaining to your chemistry teacher that the book says differently, I'm no help, all I'm doing at the moment is ionic and covalent bonding haha fun!

[Kardan]

Thanks, +Rep - I'll see if I can speak to him before the exam tomorrow.

[Josh-H]

It is (Total Mr of useful products / Total Mr of reactants) x 100

100% sure.

(A-Level chemist)

[Mitch4?]

i took chemistry a level, but im crap at it
i thought products and reactants were the same value, so it doesnt matter?
idklols

[Kardan]

i took chemistry a level, but im crap at it
i thought products and reactants were the same value, so it doesnt matter?
idklols

Yeah, that's what my Chemistry teacher said

Anyway, Atom Economy came up but it didn't require us to work it out, so it's all good. Test paper went really well.