I think we can distinguish A from B because they are totally different letters but bro what do you mean in what form of letters, is there supposed to be like an equation or something please tell me if there is so i can help you or whatever it is hope i can help you :)
Answer:
D
Explanation:
Oxygen is the 8th element in the periodic table. This means that oxygen has 8 protons and 8 electrons. In order to get the number of neutrons you take the atomic weight in this case 15.9999~16 and you subtract it by the number of protons (16-8).
The concept we are looking for here is electronegativity. This concept is a measure of how strong an atom or element can attract a pair, that is bonding, of electrons to itself.
Fluorine is the element or atom of the greatest electronegativity. Electronegativity would increase as we move left to right of the periodic table.
Question is incomplete. Complete question is attached below
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Answer: Option A: HCO3-(aq.)
Reason:
From the reaction, it can be seen that following reaction occurs in forward direct
HCO3-(aq) + H2O(l) → H2CO3(aq) + OH-(aq)
In above forward reaction, HCO3- accepts proton from H2O to generate H2CO3. Thus, according to Lowry and Bronsted theory of acid-base,
HCO3- is a base, while
H2CO3 is a conjugate acid.