# Chemistry :)

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Cr2O3 + 3CCl4 ---> 2CrCl3 + 3CCl2O

In one experiment, 6.37 grams of Cr2O3 was treated wiht excess CCl4 and yielded 8.75 grams of CrCl3. What was the percent yeild?

I have no idea how to do this. I know that percent yield is actual/theorectical yield *100.
And i know how to do this type of problem when the problem has the words is produced in it. Because what is produced is the actual yield. But how would i do this problem since it doesn't say is produced?

Can anyone help me, thanks:)

• Chemistry :) - ,

It "yielded" 8.75 g CrCl3. That means it produced that many grams. What you must do is calculate how much CrCl3 SHOULD have been formed, using 6.37 g Cr2O3 as a starting material. That amount that should have been formed is the theoretical yield.

• Chemistry :) - ,

Thank you for your help! :) You are very smart!

• Chemistry :) - ,

Not smart. Persistent.
I worked the problem and found mass CrCl3 of about 13 grams or so as the theoretical yield. Actual yield of 8.75 g which makes the % yield about 60% give or take a little. Check me out on that. Sometimes I punch the wrong numbers on the calculator.