Answer : The value of 
of the weak acid is, 4.72
Explanation :
First we have to calculate the moles of KOH.
Now we have to calculate the value of of the weak acid.
The equilibrium chemical reaction is:
Initial moles 0.25 0.03 0
At eqm. (0.25-0.03) 0.03 0.03
= 0.22
Using Henderson Hesselbach equation :
![pH=pK_a+\log \frac{[Salt]}{[Acid]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BSalt%5D%7D%7B%5BAcid%5D%7D)
![pH=pK_a+\log \frac{[HK]}{[HA]}](https://tex.z-dn.net/?f=pH%3DpK_a%2B%5Clog%20%5Cfrac%7B%5BHK%5D%7D%7B%5BHA%5D%7D)
Now put all the given values in this expression, we get:
Therefore, the value of of the weak acid is, 4.72
Answer:
1 mole
Explanation:
A mole of water molecules contains 2 moles of hydrogen atoms and 1 mole of oxygen atoms.
Answer: The charge on a sulfide ion is –2.
Explanation:
A barometer measures air pressure.
Answer:
The correct answer is - Positive charge occupies a very small volume in the atom.
Explanation:
Ernest Rutherford's experiments exhibited the presence of the nuclear core: a small region with the greater part of the mass of the atom and the positive charge.
Rutherford's gold foil analyze gave three conclusions:
- the particle is generally vacant space
- in it is a little, thick core or dense nucleus
- the core is positively charged.
