# If the percent yield of this reaction is 90%, what is the theoretical yield of the reaction if 9.0 g of H2 is produced?Answer the question using the balanced equation below: 2 K + 2 H2O → 2 KOH +...

If the percent yield of this reaction is 90%, what is the theoretical yield of the reaction if 9.0 g of H2 is produced?

Answer the question using the balanced equation below:

2 K + 2 H2O → 2 KOH + H2
If the percent yield of this reaction is 90%, what is the theoretical yield of the reaction if 9.0 g of H2 is produced? Show your work, including all conversion factors and all units.

sanjeetmanna | College Teacher | (Level 3) Assistant Educator

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Percentage yield is calculated using the mass of the actual product obtained from the experiment and the theoretical mass of the product calculated using the balanced equation of the reaction.

The general mechanism for finding percentage yield is as follows:

1.  Balance the chemical equation
2.  Find the limiting reagent
3.  Find the theoretical yield
4.  Find the actual yield
5.  Find the percentage yield

1.  Balance the chemical equation

2 K + 2 H2O → 2 KOH + H2

Theoretical yield (how much product will be synthesized in ideal conditions that is from the reaction by using limiting reactant ) and actual yield (amount producted in lab or in an experiment) is 9g of H2 and percentage yield is given 90%.

5.  Find the theoretical yield

% yield = (mass of actual yield / mass of Theoretical yield) * 100

90 = (9 g / mass of Theoretical yield) * 100

0.9 = 9 g / mass of Theoretical yield

mass of Theoretical yield = 9/0.9

mass of Theoretical yield = 10 gm.