I think B, don’t come at me if I’m wrong
Answer:
The mass of nitrogen gas will be 31,3 g
Explanation:
We calculate the weight of 1 mol of N2 (nytrogen gas):
Weight 1 mol N2= 2 (weight N)= 2 x 14 g/mol = 28g/mol
The conditions STP are 1 atm of pressure and 273K of temperature. We use the formula:
PV=nRT
1 atmx 25,0L= n x0,082 l atm/K mol x 272 K
n= 1 atmx 25,0L/0,082 l atm/K mol x 272 K= 1, 12 mol
1 mol N2-----28 g
1,12mol N2---x= (1,12mol N2 x28g)/1 mol N2= 31, 3 g
H - hydrogen is a chemical element
O - oxygen is a chemical element
H₂ - hydrogen is a chemical substance wish a molecule comprising two atoms
O₂ - oxygen is a chemical substance wish a molecule comprising two atoms
H₂O - water is a chemical substance wish a molecule comprising two atoms of hydrogen and one atom of oxygen
M₀=2.643 g
m₁=2.090 g
m(H₂O)=m₀-m₁
w(H₂O)=m(H₂O)/m₀=(m₀-m₁)/m₀
w(H₂O)=(2.643-2.090)/2.643=0.2092 (20.92%)
20.92%