N2 + 3H2 --> 2NH3
If 28 grams of nitrogen reacts with excess hydrogen, how many grams of NH3 will be formed?
N2 + 3H2 --> 2NH3
moles N2 = grams/molar mass = (28/2*14) = 1.0
Convert this to mols NH3 produced by
1.0 mole N2 x (2 moles NH3/1 mol N2) b= 1.0 x 2/1 = 2.0
Then grams NH3 = mols NH3 x molar mass NH3 = ?
To find the number of grams of NH3 formed, you need to use the concept of stoichiometry.
Step 1: Determine the molar mass of each compound involved in the reaction.
The molar mass of N2 (nitrogen gas) is 28 grams/mol since the periodic table states that nitrogen has an atomic weight of 14 g/mol and there are two nitrogen atoms in N2.
The molar mass of H2 (hydrogen gas) is 2 grams/mol since hydrogen has an atomic weight of 1 g/mol and there are two hydrogen atoms in H2.
The molar mass of NH3 (ammonia) is 17 grams/mol. Nitrogen has an atomic weight of 14 g/mol, and hydrogen has an atomic weight of 1 g/mol, so you add them together: (14 g/mol + 3(1 g/mol)) = 17 g/mol.
Step 2: Convert the given mass of nitrogen (N2) to moles.
To convert grams of a substance to moles, you need to use the molar mass. Given that you have 28 grams of nitrogen, you can calculate the number of moles using the formula:
moles = mass / molar mass
moles of nitrogen = 28 g / 28 g/mol = 1 mol
Step 3: Use the balanced equation to determine the mole ratio.
From the balanced equation, you know that 1 mole of nitrogen reacts with 3 moles of hydrogen to produce 2 moles of ammonia.
Step 4: Use the mole ratio to find the moles of NH3 produced.
Using the mole ratio from step 3, you can determine the moles of NH3 by multiplying the moles of nitrogen by the ratio:
moles of NH3 = moles of nitrogen × (2 moles of NH3 / 1 mole of N2) = 1 mol × 2 = 2 mol
Step 5: Convert moles of NH3 to grams of NH3.
To convert moles of NH3 to grams, you again use the molar mass:
mass = moles × molar mass
mass of NH3 = 2 mol × 17 g/mol = 34 grams
Therefore, if 28 grams of nitrogen reacts with excess hydrogen, 34 grams of NH3 will be formed.