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A level chemistry HELP

I know the answer (D) just not how you get to it. I know the equation but damn whats all this organic talk. It doesn't give you the desired mass either

Which chemical process is the most sustainable in terms of atom economy of the organic product?
(a) CO2 + 3H2 -> CH3OH + H2O
(b) CH3CH2OH + NaCl + H2SO4 -> CH3CH2Cl + NaHSO4 + H2O
(c) CH3CH2Br + NaOH -> CH3CH2OH + NaBr
(d) CH3CH2CH2CH2OH -> CH3CH2CH=CH2 + H2O

Reply 1

MinMin25

the organic product is going to be the one with the carbons and hydrogens and such. so in this case:
(a) CH₃OH
(b) CH₃CH₂Cl
(c) CH₃CH₂OH
(d) CH₃CH₂CH=CH₂
since it's a multiple choice, i'll show you a shortcut!

atom economy has the equation 'M_r of desired product/ sum of Mrof all products x 100' and so you're gonna be looking for a bigger number on top to maximise the percentage. in this case, you don’t need the desired mass, just M_r. already, looking at (d) the organic product is the bigger one of the two products, so you'll get a high percentage. you dont need to calculate the other ones once you spot this, as (a) has a relatively small organic product, (b) has many other products which decrease atom economy, and (c) is similar to (b). for d, you get:
(12 x 4) + (1 x 8) / (12 x 4) + (1 x 8) + 18 then x100 to get 75.68%, the highest atom economy.

Reply 2

AB27

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Reply 3

username5816334

Original post by MinMin25

the organic product is going to be the one with the carbons and hydrogens and such. so in this case:
(a) CH₃OH
(b) CH₃CH₂Cl
(c) CH₃CH₂OH
(d) CH₃CH₂CH=CH₂
since it's a multiple choice, i'll show you a shortcut!

atom economy has the equation 'M_r of desired product/ sum of Mr of all products x 100' and so you're gonna be looking for a bigger number on top to maximise the percentage. in this case, you don’t need the desired mass, just M_r. already, looking at (d) the organic product is the bigger one of the two products, so you'll get a high percentage. you dont need to calculate the other ones once you spot this, as (a) has a relatively small organic product, (b) has many other products which decrease atom economy, and (c) is similar to (b). for d, you get:
(12 x 4) + (1 x 8) / (12 x 4) + (1 x 8) + 18 then x100 to get 75.68%, the highest atom economy.

THANK YOU. I was struggling with the wording. By sustainable it means the atom economy is larger correct? With the equation you wrote for d why did you add 18 on the end. Sorry for asking so much ://////