Calculating yield based on weight

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Andrew4d7
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Calculating yield based on weight

Post by Andrew4d7 »

Hello peeps.

How should I calculate a yield based on weight?

Lets say I have put in 25g of Na2WO4, mixed it up with H3PO4 and crashed out the compound with KCl.

Compounds formula K6[P2W18O64]. Yield = 7g

I want to calculate yield based on the weight of W.

Thanks in advance. :wink:
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ChenBeier
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Post by ChenBeier »

Calculate: m of your product divided by molar mass of the product gives the moles.
The mass of tungsten is then calculated: moles multiplied by the molar mass of tungsten times 18

7g /M(K6[P2W18O64]) = x g /(18* M(W))
Andrew4d7
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Post by Andrew4d7 »

Thanks for the quick reply.

So I calculated 7g/M(K6[P2W18O64]) = 0.0015 mol
18*M(W) = 3311.11 g/mol

Then x = 0.0015 mol * 3311.11 g/mol = 4.96g

As I understand x is W weight in my product mixture. How do I calculate the yield percentage now?

Is it m(W product mixture) / m(W in 25g of Na2WO4) * 100% ?
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ChenBeier
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Post by ChenBeier »

No you have to calculate the m of W in Na2WO4 first.

Then you divide this value by the m of W of your product.
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