Answer:
The volume of the vessel is 250 L
Partial pressure of hydrogen = 189 torr
Explanation:
Using Boyle's law

Given ,
V₁ = 20.0 L
V₂ = ?
P₁ = 25 atm
P₂ = 2 atm
Using above equation as:




<u>The volume of the vessel is 250 L.</u>
According to Dalton's law of partial pressure:-

So, according to definition of mole fraction:

Also,
Mole fraction of H₂ = 1 - Mole fraction of He = 1 - 0.75 = 0.25
So,
Total pressure = 756 torr
Thus,

<u>Partial pressure of hydrogen = 189 torr.</u>
Answer:
Natural Gas is a fossil energy source that formed deep beneath the Earth's surface. It is used in power plants to generate electricity by burning natural gas as their fuel.
Explanation: I hope this helped :)
<span>1.54 x 10^5 mg
The atomic weight of nickel is 58.6934
Since you have 2.63 moles, the mass will be
2.63 * 58.6934 = 154.3636 grams.
Multiply by 1000 to get milligrams
154.3636 * 1000 = 154363.6 g
Convert to scientific notation
1.543636 x 10^5
Look at the available options and see what matches.
3.56 x 10^5 mg ; Nope, way too big
1.54 x 10^5 mg; Matches to the number of significant figures given.
2.23 x 10^4 mg; Nope, way too small
129 mg; Nope, way too small.</span>