N2 + 2O2 -->2 NO2

Suppose 31.25 g of N and 44.0 G of O react

A. Calculate the mass of Nitrogen Dioxide formed.
B. Which reactant is the limiting reactant?
C. Calculate the mass of the excess reactant left after the reaction.
D. Find the % yield if 52.3 g of NO2 is produced.

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To answer these questions, we need to calculate the number of moles of each reactant and then determine the limiting reactant. The limiting reactant is the one that will be completely consumed and limits the amount of product that can be formed. Additionally, we will calculate the mass of Nitrogen Dioxide formed, the mass of the excess reactant remaining, and the percent yield of NO2.

Given:
Mass of N = 31.25 g
Mass of O = 44.0 g

A. Calculate the mass of Nitrogen Dioxide formed:
To calculate the mass of Nitrogen Dioxide formed, we need to determine the limiting reactant and then use stoichiometry to calculate the mass of the product formed.

First, calculate the number of moles of N:
Molar mass of N = 14.01 g/mol
Moles of N = Mass of N / Molar mass of N

Moles of N = 31.25 g / 14.01 g/mol

Next, calculate the number of moles of O:
Molar mass of O2 = 32.0 g/mol
Moles of O2 = Mass of O2 / Molar mass of O2

Moles of O2 = 44.0 g / 32.0 g/mol

Now, we need to determine the limiting reactant. To do this, we compare the mole ratios from the balanced equation, which is 1:2 for N2 to O2.

Moles of N / Coefficient of N = Moles of O / Coefficient of O

Moles of N / 1 = Moles of O / 2

From the previous calculations, we have the following moles:
Moles of N = 31.25 g / 14.01 g/mol
Moles of O = 44.0 g / 32.0 g/mol

Plugging the values into the equation:

31.25 g / 14.01 g/mol = Moles of O / 2

Now, solve for Moles of O:

Moles of O = (31.25 g / 14.01 g/mol) * 2

Now we have the moles of each reactant. The limiting reactant is the one that has fewer moles, as it will be completely consumed in the reaction. Compare the moles of N and O to determine the limiting reactant.

If the moles of N are smaller, N is the limiting reactant.
If the moles of O are smaller, O is the limiting reactant.

Once we determine the limiting reactant, we can calculate the moles of Nitrogen Dioxide formed using the stoichiometry from the balanced equation.

Moles of NO2 = Moles of limiting reactant * Coefficient of NO2

Finally, calculate the mass of Nitrogen Dioxide formed by multiplying the moles by the molar mass of Nitrogen Dioxide.

Mass of NO2 = Moles of NO2 * Molar mass of NO2

B. Which reactant is the limiting reactant:
Compare the moles of N and O calculated earlier to determine the limiting reactant.

C. Calculate the mass of the excess reactant left after the reaction:
The excess reactant is the reactant that is not completely consumed and is left over after the reaction. To calculate the mass of the excess reactant, we first determine the moles of the limiting reactant in the reaction.

Moles of limiting reactant = Mass of limiting reactant / Molar mass of limiting reactant

Next, calculate the moles of the excess reactant by subtracting the moles of the limiting reactant from the initial moles of the excess reactant.

Moles of excess reactant = Initial moles of excess reactant - Moles of the limiting reactant

Finally, calculate the mass of the excess reactant by multiplying the moles by the molar mass of the excess reactant.

Mass of excess reactant = Moles of excess reactant * Molar mass of excess reactant

D. Find the percent yield if 52.3 g of NO2 is produced:
Percent yield is the ratio of the actual yield (52.3 g) to the theoretical yield, which is the maximum amount of product that can be formed based on the limiting reactant. To calculate the theoretical yield, we first convert the mass of the limiting reactant to moles. Then we use stoichiometry to determine the moles of NO2 that can be formed based on the balanced equation. Finally, we convert moles of NO2 to grams using the molar mass of NO2.

Once we calculate the theoretical yield, we can calculate the percent yield using the actual yield and the theoretical yield.

Percent yield = (Actual yield / Theoretical yield) * 100