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Chemistry coefficients

When calculating atom economy do you always times the Mr by the coefficient? Confused as when i do other calcs involving Mr you do not use the coefficient unless you are calculating the mole ratio.
Original post by BCGscience
When calculating atom economy do you always times the Mr by the coefficient? Confused as when i do other calcs involving Mr you do not use the coefficient unless you are calculating the mole ratio.


Yes.

For a reaction aA + bB + (…) —> cC + dD + (…), the atom economy with respect to C is:

(c x (Mr of C) x 100) / (a x (Mr of A) + b x (Mr of B) + (…))

Where the denominator includes only species on the reactants side OR alternatively the products side
(edited 1 year ago)
Original post by TypicalNerd
Yes.

For a reaction aA + bB + (…) —> cC + dD + (…), the atom economy with respect to C is:

(c x (Mr of C) x 100) / (a x (Mr of A) + b x (Mr of B) + (…))

Where the denominator includes only species on the reactants side OR alternatively the products side

Thanks!

What other cases would you need to times the Mr by the coefficient in A level chem? Or is there a simple chemical explanation for needing to do this?
Original post by BCGscience
Thanks!

What other cases would you need to times the Mr by the coefficient in A level chem? Or is there a simple chemical explanation for needing to do this?


This and any calculations requiring mole ratios are the only examples that come to mind.

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