I am also taking the test, but I think it's C. But I'm not exactly sure
Answer:
1.7927 mL
Explanation:
The mass of solid taken = 4.75 g
This solid contains 21.6 wt% 
, thus,
Mass of = 
= 1.026 g
Molar mass of = 261.337 g/mol
The formula for the calculation of moles is shown below:
Thus,
Considering the reaction as:
1 moles of react with 1 mole of 
Thus,
0.003926 mole of react with 0.003926 mole of
Moles of = 0.003926 mole
Also, considering:
Molarity = 2.19 M
So,
Volume = 0.0017927 L
Also, 1 L = 1000 mL
<u>So, volume = 1.7927 mL</u>
The number of moles in a substance may be calculated using:
Moles = mass / molecular mass
The molecular mass of CH₂Cl₂ is:
12 + 2 * 1 + 2 * 35.5
= 85 grams / mole
Moles = 76.1 / 85
Moles = 0.895
There are 0.90 moles of CH₂Cl₂ present in 76.1 grams.
Answer:
Kc=[[CO][H2]3[CH4][H2O]
3.90=(0.30)(0.10)3[CH4]×0.02
[CH4]=0.023.90×0.30×(0.10)3=5.85×10−2 M
Thus, the concentration of methane in the mixture is 5.85×10−2 M.
For a 100-g compound, we would have 2 g H, 32.7 g S, and 65.3 g O. We then divide each of these masses by their molar masses:
2 g H / 1.01 g/mol = 1.98 mol H
32.7 g S / 32.07 g/mol = 1.0196 mol S
65.3 g O / 16.00 g/mol = 4.08125 mol O
We then divide each amount of moles by the smallest of them, which is the 1.0196 from S:
1.98 mol H / 1.0196 mol S = 1.94 H ~ 2 H
1.0196 mol S / 1.0196 mol S = 1 S
4.08125 mol O / 1.0196 mol S = 4 O
So the empirical formula of the compound is H2SO4.
