## Me podrian ayudar

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Maite2019
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Posts: 4
Joined: Wed Mar 31, 2021 10:52 pm

### Me podrian ayudar

A 30,0 g de una muestra de ZnCl2 se le agrega exceso de H3PO4 obteniéndose 15,5 g de Zn3(PO4)2.

Calcule los equivalentes de H3PO4 que deben haber reaccionado si el rendimiento fue del 90,0 %
Maite2019
Newbie
Posts: 4
Joined: Wed Mar 31, 2021 10:52 pm

### Re: Me podrian ayudar

Excess H3PO4 is added to 30.0 g of a sample of ZnCl2, obtaining 15.5 g of Zn3 (PO4) 2.

Calculate the H3PO4 equivalents that must have reacted if the yield was 90.0%
ChenBeier
Distinguished Member
Posts: 703
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Me podrian ayudar

What is your own work. Where do you have problems.
Maite2019
Newbie
Posts: 4
Joined: Wed Mar 31, 2021 10:52 pm

### Re: Me podrian ayudar

I don't know how to get the excess H3PO4 ...
Idk to pose the first part of the problem
ChenBeier
Distinguished Member
Posts: 703
Joined: Wed Sep 27, 2017 7:25 am
Location: Berlin, Germany

### Re: Me podrian ayudar

Excess means there is enough phosphoric acid.
First develop the chemical equation.
Then calculate the mol of zincphosphate .
Check is enough zinc chloride available.
From zinc phosphate calculate back how much phosphoric is needed.
Calculate with the yield.
Maite2019
Newbie
Posts: 4
Joined: Wed Mar 31, 2021 10:52 pm

Thank uuu