Determine the percent yeild of:
KCl3(s)--> KCl(s)+ O2(g)
2.14g of KCl3 produces 0.67 of O2
I get 123% when the correct answer is 80%
My work:
KCl3: mm = 122.45, n =0.017
Theoretical yield: .017mol * 32g/mol
Pecent Yield: 0.67g/ 0.544g *100% = 123%
Thanks for showing your work. It helped me spot the error right off. You didn't balance the equation. Also note that I corrected the formula for KClO3 but you have the right moles so you must have used the correct molar mass.
2KClO3 ==> 2KCl + 3O2
moles KClO3 = 2.14/122.5 = 0.0175
moles oxygen = 0.0175 x (3 moles O2/2 moles KClO3) = 0.0175 x (3/2) = 0.0262.
grams O2 = moles O2 x molar mass = 0.0262 x 32 = 0.838 g O2 for theoretical yield.
Use that number with 0.67 and see if it's ok. I get 79.9% which rounds to 80% to two significant figures (which is all we are allowed with the 0.67).
First, start with a balanced equation
2KClO3(s)--> 2KCl(s)+ 3O2(g)
2KClO3: mm=2(39+35.5+16*3)= 245
3O2: mm = 3(2*16) = 96
Theoretical yield
=2.14*(96/245)
=0.839
Actual yield
=0.67
Percent yield
=0.67/0.839
=80%
80.% (to two significant figures)
To determine the percent yield, you need to compare the actual yield (0.67g of O2) with the theoretical yield, which is calculated based on the stoichiometry of the reaction.
First, let's calculate the theoretical yield of O2:
1 mol of KCl3 produces 1 mol of O2 (according to the balanced equation).
From your calculation, you correctly determined that the number of moles of KCl3 is 0.017 mol.
The molar mass of O2 is 32 g/mol. So, the theoretical yield of O2 can be calculated as follows:
Theoretical yield of O2 = 0.017 mol * 32 g/mol = 0.544 g
Now, let's calculate the percent yield:
Percent Yield = (Actual yield / Theoretical yield) * 100%
Plugging in the values:
Actual yield = 0.67 g
Theoretical yield = 0.544 g
Percent Yield = (0.67 g / 0.544 g) * 100% = 123%
Based on your calculation, you obtained a percent yield of 123%. However, this result is incorrect. The correct percent yield is 80%.
To troubleshoot the error, there might have been a mistake in your calculation of the actual yield. Double-check your numbers to ensure accuracy.