What is the maximum mass of product that can be formed when 76.0 g of solid zinc and 17.5 g nitrogen gas react?
i like you to answer my guestion
This is a limiting reagent problem.
1. Write and balance the equation.
3Zn + N2 ==> Zn3N2
2. Convert 76 g Zn to moles. moles = grams/molar mass
3. Convert 17.5 g N2 gas to moles.
4a. Using the coefficients in the balanced equation, convert moles Zn to moles of the product.
4b. Same procedure, convert moles N2 to moles of the product.
4c. Likely the answers to 4a and 4b will not be the same. One must be incorrect. The correct one is ALWAYS the smaller value.
5. Using the value from 4c, convert moles Zn3N2 to grams.
grams = moles x molar mass.
Okay thanks. I worked it out and got the correct answer of 86.8 grams for the mass product.
This is a typical limiting reagent problem You can take this procedure and apply it to the earlier problem you had.
To determine the maximum mass of product that can be formed during a chemical reaction, you first need to identify and balance the chemical equation for the reaction.
In this case, the reaction is between solid zinc (Zn) and nitrogen gas (N₂). The balanced chemical equation for this reaction is:
2Zn + N₂ → 2ZnN
From the balanced equation, we can see that 2 moles of zinc (Zn) react with 1 mole of nitrogen gas (N₂) to produce 2 moles of zinc nitride (ZnN).
Next, you need to calculate the number of moles of each reactant. To do this, divide the given masses of zinc and nitrogen gas by their respective molar masses.
The molar mass of zinc (Zn) is 65.38 g/mol, and the molar mass of nitrogen (N₂) is 28.02 g/mol.
For solid zinc:
76.0 g (mass) / 65.38 g/mol (molar mass) = 1.16 mol
For nitrogen gas:
17.5 g (mass) / 28.02 g/mol (molar mass) = 0.625 mol
Since the stoichiometric ratio between zinc (Zn) and nitrogen gas (N₂) is 2:1, we have an excess of zinc. Therefore, the limiting reactant is nitrogen gas (N₂), and we will use its number of moles for further calculations.
The balanced equation shows that 1 mole of nitrogen gas (N₂) reacts to produce 2 moles of zinc nitride (ZnN). Therefore, using the mole ratio, we can calculate the number of moles of zinc nitride produced:
0.625 mol (moles of N₂) × (2 mol ZnN / 1 mol N₂) = 1.25 mol ZnN
Finally, to find the maximum mass of the product, we multiply the number of moles of zinc nitride by its molar mass, which is 114.41 g/mol:
1.25 mol (moles of ZnN) × 114.41 g/mol (molar mass of ZnN) = 143.01 g
Therefore, the maximum mass of zinc nitride that can be formed is approximately 143.01 grams.