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=
![\dfrac{[H^{+}] [A^{-}]}{[HA]}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5BH%5E%7B%2B%7D%5D%20%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
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Explanation:
- When an aqueous solution of a certain acid is prepared it is dissociated is as follows-
⇄ 
Here HA is a protonic acid such as acetic acid, 
- The double arrow signifies that it is an equilibrium process, which means the dissociation and recombination of the acid occur simultaneously.
- The acid dissociation constant can be given by -
= ![\dfrac{[H^{+}] [A^{-}]}{[HA]}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5BH%5E%7B%2B%7D%5D%20%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
- The reaction is can also be represented by Bronsted and lowry -
⇄ ![[H_3O^+] [A^-]](https://tex.z-dn.net/?f=%5BH_3O%5E%2B%5D%20%5BA%5E-%5D)
- Then the dissociation constant will be
= ![\dfrac{[H_3O^{+}] [A^{-}]}{[HA]}](https://tex.z-dn.net/?f=%5Cdfrac%7B%5BH_3O%5E%7B%2B%7D%5D%20%5BA%5E%7B-%7D%5D%7D%7B%5BHA%5D%7D)
Here,
is the dissociation constant of an acid.
<h2>Nuclear Fission and Nuclear Fusion - Option C</h2>
Nuclear fission and nuclear fusion both of these processes can provide energy. Nuclear fission is the process in which heavy nucleus splits into smaller parts. When they split into smaller particles then it releases energy.
On the other hand, nuclear fusion is the process in which small particles fuse together to form a heavy nucleus. With the formation of heavy nucleus, it also provides energy.
Therefore, both these processes release or provide energy.
Answer: B. The element called tin is a metal with the chemical symbol Sn.
Explanation:
A is incorrect because Ni is Nickel, not Niobium.
C is incorrect because Carbon is a nonmetal and its symbol is C, not Cr.
D is incorrect because Copper's symbol is Cu, not Ce.
E is incorrect because As is the symbol for Arsenic, not Astatine.
Answer:
iodine.
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