Answer : The pH of the solution is, 2.67
Explanation :
The equilibrium chemical reaction is:

Initial conc. 0.450 0 0
At eqm. (0.450-x) x x
As we are given:

The expression for equilibrium constant is:

Now put all the given values in this expression, we get:


The concentration of
= x = 0.00212 M
Now we have to calculate the pH of solution.
![pH=-\log [H^+]](https://tex.z-dn.net/?f=pH%3D-%5Clog%20%5BH%5E%2B%5D)


Therefore, the pH of the solution is, 2.67
If you’re talking about noble gases, the answer would be A. Since noble gases already have 8 electrons, they don’t tend to form chemical bonds. And elements need just 8 electrons on there shells to be stable.
Answer: Thus the correct option is D. All of the above describe a mole
Explanation:
According to avogadro's law, 1 mole of every substance weighs equal to molecular mass in grams.
1 mole of every substance contains avogadro's number
of particles.
Mole is the S.I unit for measuring the amount of substance. It is often used to measure large number of particles.
Thus the correct option is D. All of the above describe a mole