Question:
Zinc metal is added to hydrochloric acid to generate hydrogen gas and is collected over a liquid whose vapor pressure is the same as pure water at 20.0 degrees C (18 torr). The volume of the mixture is 1.7 L and its total pressure is 0.987 atm. Determine the number of moles of hydrogen gas present in the sample.
A. 0.272 mol
B. 0.04 mol
C. 0.997 mol
D. 0.139 mol
E. 0.0681 mol
Answer:
The correct option is;
E. 0.0681 mol
Explanation:
The equation for the reaction is
Zn + HCl = H₂ + ZnCl₂
Vapor pressure of the liquid = 18 torr = 2399.803 Pa
Total pressure of gas mixture H₂ + liquid vapor = 0.987 atm
= 100007.775 Pa
Therefore, by Avogadro's law, pressure of the hydrogen gas is given by the following equation
Pressure of H₂ = 100007.775 Pa - 2399.803 Pa = 97607.972 Pa
Volume of H₂ = 1.7 L = 0.0017 m³
Temperature = 20 °C = 293.15 K
Therefore,
Therefore, the number of moles of hydrogen gas present in the sample is n ≈ 0.0681 moles.
Answer:
yeah.. u cant only if heated the iced tea, breaking the sugar cube up has no effect on the dissolving process.
Answer:
C. 2.3 moles of oxygen (O2)
Explanation:
Answer:
The final concentration of KCl is 4%
Explanation:
This is a solution with KCl and water.
12% it's a way of concentration that indicates, that in 100 mL of solution, we have 12 g of solute.
If we add 200 mL to this solution, we also have 12 g of solute but now, we have to calculate the new concentration.
New volume = 100 mL + 200 mL → 300 mL
Let's make a rule of three
In 300 mL we have 12 g of solute
In 100 mL we have (100 .12) / 300 = 4
I think the answer is answer number 2. because in Daltons atomic theory you cannot have an element that magically appears out of no where and the same that goes into it the same should be equivalent that comes out. I hope that helps?