What mass of Na2S is produced when 20g of sodium reacts with excess sulfur?
2Na + S ==> Na2S
mols Na = grams/atomic mass = ?
Using the coefficients in the balanced equation, convert mols Na to mols Na2S. That's ?mols Na x (1 mol Na2S/2 mols S)= ?mols Na x 1/2 = ?
Then grams Na2S = mols Na2S x molar mass Na2S
48.39 g Na2S
To determine the mass of Na2S produced, we need to first balance the equation for the reaction between sodium and sulfur:
2 Na + S --> Na2S
From the balanced equation, we can see that the ratio between sodium (Na) and sodium sulfide (Na2S) is 2:1. This means that for every 2 moles of Na, we will get 1 mole of Na2S.
To calculate the number of moles of Na, we need to use its molar mass. The molar mass of Na is 22.99 g/mol.
Let's calculate the number of moles of Na:
moles of Na = mass of Na / molar mass of Na
moles of Na = 20 g / 22.99 g/mol
moles of Na = 0.870 mol
According to the balanced equation, the mole ratio between Na and Na2S is 2:1. Since we have 0.870 mol of Na, we will have half that amount of Na2S:
moles of Na2S = moles of Na / 2
moles of Na2S = 0.870 mol / 2
moles of Na2S = 0.435 mol
Now we need to convert moles of Na2S to mass using its molar mass. The molar mass of Na2S is the sum of the atomic masses of Na (22.99 g/mol) and S (32.06 g/mol):
molar mass of Na2S = 22.99 g/mol + 32.06 g/mol
molar mass of Na2S = 54.05 g/mol
Finally, let's calculate the mass of Na2S:
mass of Na2S = moles of Na2S * molar mass of Na2S
mass of Na2S = 0.435 mol * 54.05 g/mol
mass of Na2S = 23.48 g
Therefore, approximately 23.48 grams of Na2S will be produced when 20 grams of sodium reacts with excess sulfur.