Chlorine is the correct answer so A
Answer : The mass of nitric acid is, 214.234 grams.
Solution : Given,
Moles of nitric acid = 3.4 moles
Molar mass of nitric acid = 63.01 g/mole
Formula used :

Now put all the given values in this formula, we get the mass of nitric acid.

Therefore, the mass of nitric acid is, 214.234 grams.
To determine the empirical formula of the compound, we assume a basis of 100 g of this compound. We calculate as follows:
C = 68.75 g
H = 10.90 g
O = 20.35 g
We convert these mass to moles,
C = 68.75 g / 12.01 g/mol = 5.72 mol
H = 10.90 g / 1.01 g/mol = 10.79 mol
O = 20.35 g / 16 g/mol = 1.27 mol
C = 5.72 mol / 1.27 mol = 5
H = 10.79 mol / 1.27 mol = 8
O = 1.27 mol / 1.27 mol = 1
C5H8O
<span>69.3 g
First, determine the molar masses involved:
Atomic weight iron = 55.845
Atomic weight carbon = 12.0107
Atomic weight oxygen = 15.999
Molar mass Fe2O3 = 2 * 55.845 + 3 * 15.999 = 159.687 g/mol
Molar mass CO = 12.0107 + 15.999 = 28.0097 g/mol
Determine how many moles of each reactant we have
Moles Fe2O3 = 189 g / 159.687 g/mol = 1.18356535 mol
Moles CO = 63.0 g / 28.0097 g/mol = 2.249220806 mol
For every mole of Fe2O3, we need 3 moles of CO. So let's see how many moles of Fe2O3 is consumed by dividing moles CO by 3.
2.249220806 mol / 3 = 0.749740269 mol
So we'll be consuming 0.749740269 moles of Fe2O3, subtract that from what we started with
1.18356535 mol - 0.749740269 mol = 0.433825081 mol
Now multiply by the molar mass of Fe2O3
0.433825081 mol * 159.687 g/mol = 69.27622574 g
Rounding to 3 significant figures gives 69.3 g</span>