very hot sinc will react with steam to form zinc oxide and hydrogen. If 5.4 liters of hydrogen was used to use up 20 g of zinc completely. What is the percent yield of this process
Strange wording. I assume you want to know % yield when 20g Znb produced 5.4L H2.
Zn + H2O ==> ZnO + H2
mols Zn = grams/atomic mass
Use the coefficients in the balanced equation to convert mols Zn to mols H2. Note that is a 1:1 conversion.
Then convert mols Zn to L.
1 mol occupies 22.4L. This is the theoretical yield The actual yield 5.4 L.
%yield = (actual yield/theor yeild)*100 = ?
To find the percent yield of a chemical reaction, you need to compare the actual yield (the amount of product obtained in the experiment) to the theoretical yield (the maximum amount of product that can be obtained based on the reactants used).
In this case, we are given that 5.4 liters of hydrogen gas is used up to completely react with 20 g of zinc. We can use the balanced chemical equation to determine the theoretical yield.
The balanced chemical equation for the reaction is:
Zn + H2O -> ZnO + H2
From the equation, we know that the stoichiometric ratio between zinc (Zn) and hydrogen gas (H2) is 1:1. That means 1 mole of zinc reacts with 1 mole of hydrogen gas to produce 1 mole of zinc oxide (ZnO) and 1 mole of hydrogen gas.
First, let's calculate the number of moles of hydrogen gas used.
Using the Ideal Gas Law, we can convert the given volume of hydrogen gas into moles. The molar volume of a gas at standard temperature and pressure (STP) is 22.4 liters/mol.
5.4 liters of hydrogen gas = 5.4/22.4 moles of hydrogen gas
Next, we need to determine the number of moles of zinc used.
The molar mass of zinc (Zn) is 65.38 g/mol. By using the molar mass, we can convert the given mass of zinc into moles.
20 g of zinc = 20/65.38 moles of zinc
Since the stoichiometric ratio is 1:1 between zinc and hydrogen gas, we can compare the moles of zinc to the moles of hydrogen gas.
From the above calculations, we see that 1 mole of zinc reacts with 1 mole of hydrogen gas. Therefore, the moles of zinc used is also 5.4/22.4.
Now, we can calculate the theoretical yield of zinc oxide.
The molar mass of zinc oxide (ZnO) is 81.38 g/mol (65.38 g/mol for Zn + 16 g/mol for O).
Theoretical yield of ZnO = (5.4/22.4) moles of Zn x 81.38 g/mol
Finally, calculate the percent yield using the actual yield and theoretical yield.
Percent yield = (Actual yield / Theoretical yield) x 100
However, in the given information, we don't have the actual yield. To determine the percent yield, we need to know the amount of zinc oxide obtained in the reaction. Without that information, it is not possible to calculate the percent yield.