Number of moles of oxygen = x
number of moles of nitrogen = y
x = 2y
initial pressure, p1 = 0.8 atm
final pressure, p2 = 1.10 atm
At constant volume and temperature p1 / n1 = p2 / n2
=> p1 / p2 = n1 / n2
n1 = x + y = 2y + y = 3y
n2 = 0.2 + 3y
=> p1 / p2 = 3y / (0.2 + 3y)
=> 0.8 / 1.10 = 3y / (0.2 + 3y)
=> 0.8 (0.2 + 3y) = 1.10 (3y)
0.16 + 2.4y = 3.3y
=> 3.3y - 2.4y = 0.16
=> 0.9y = 0.16
=> y = 0.16 / 0.9
=. x = 2*0.16/0.9 = 0.356
Answer: 0.356 moles O2
Answer:
The concentrations are :
![[HAsc^-]=0.000702 M](https://tex.z-dn.net/?f=%5BHAsc%5E-%5D%3D0.000702%20M)
![[Asc^{2-}]=5.92\times 10^{-8} M](https://tex.z-dn.net/?f=%5BAsc%5E%7B2-%7D%5D%3D5.92%5Ctimes%2010%5E%7B-8%7D%20M)
The pH of the solution is 3.15.
Explanation:

Initial
c 0 0
Equilibrium
c-x x x
![K_{a1}=\frac{[HAs^-][H^+]}{[H_2Asc]}](https://tex.z-dn.net/?f=K_%7Ba1%7D%3D%5Cfrac%7B%5BHAs%5E-%5D%5BH%5E%2B%5D%7D%7B%5BH_2Asc%5D%7D)


Solving for x:
x = 0.000702 M
![[HAsc^-]=0.000702 M](https://tex.z-dn.net/?f=%5BHAsc%5E-%5D%3D0.000702%20M)

Initially
x 0 0
At equilibrium ;
(x - y) y y
![K_{a2}=\frac{[As^{2-}][H^+]}{[HAsc^-]}](https://tex.z-dn.net/?f=K_%7Ba2%7D%3D%5Cfrac%7B%5BAs%5E%7B2-%7D%5D%5BH%5E%2B%5D%7D%7B%5BHAsc%5E-%5D%7D)


Putting value of x = 0.000702 M


![[Asc^{2-}]=5.92\times 10^{-8} M](https://tex.z-dn.net/?f=%5BAsc%5E%7B2-%7D%5D%3D5.92%5Ctimes%2010%5E%7B-8%7D%20M)
Total concentration of ![[H^+]=x+y=0.000702 M+5.92\times 10^{-8} M=7.0206\times 10^{-4} M](https://tex.z-dn.net/?f=%5BH%5E%2B%5D%3Dx%2By%3D0.000702%20M%2B5.92%5Ctimes%2010%5E%7B-8%7D%20M%3D7.0206%5Ctimes%2010%5E%7B-4%7D%20M)
The pH of the solution :
![pH=-\log[H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%5BH%5E%2B%5D)

Answer:
d. Radon-222
Explanation:
²²⁶₈₈Ra → ²²²₈₆Rn + ⁴₂He
Alpha particle is a helium nucleus with mass number 4 and atomic number 2. According to the law of conversation of mass, the sum of the mass number and atomic number must be equal on both side of the reaction.
Since the mass number of Ra is 226 and that of He is 4. The mass number of the unknown element must be 226 - 4 = 222.
Since the atomic number of Ra is 88 and that of He is 2. The atomic number of the unknown element must be 88 - 2 = 86.
Now looking in the periodic table Radon is the only element with atomic number 86.
Answer:
Combining the two clear colorless liquids is a chemical change.
Explanation:
Because a different solid substance is formed. Tell students that a precipitate is an insoluble solid that forms when two solutions are combined and react chemically. Insoluble means that the solid will not dissolve.
Cardenolides, with the chemical formula CH₁₈C₂₀H₁₅CHCO₂ have (D) 23 carbon atoms, 34 hydrogen atoms, and 2 oxygen atoms.
Milkweed contains a poison known as cardenolides. The chemical formula for cardenolides CH₁₈C₂₀H₁₅CHCO₂.
The subscripts in the formula represent the atomicities, that is the number of atoms of each element in each part of the formula.
We can calculate the total number of atoms of each element by adding its atomicities.
<h3>Carbon atoms</h3>

<h3>Hydrogen atoms</h3>

<h3>Oxygen atoms</h3>

Cardenolides, with the chemical formula CH₁₈C₂₀H₁₅CHCO₂ have (D) 23 carbon atoms, 34 hydrogen atoms, and 2 oxygen atoms
Learn more: brainly.com/question/13348838