Acids And Bases

According to Lewis, base is a substance which donate a pair of electrons. is a Lewis base because it has a pair of electron.

At , of water is . At higher temperature, dissociates more to give larger concentration of ions. will be less than

Step 1: Understand the Lewis concept.
The Lewis concept defines acids as electron-pair acceptors and bases as electron-pair donors.
This concept can explain the behavior of bases, as they are capable of donating an electron pair.
Step 2: Identify the correct option.
According to the Lewis concept, bases donate electron pairs, while acids accept electron pairs.
Protonic acids (as per Brønsted-Lowry theory) and salts are not explained in terms of electron pair donation or acceptance.

Step 1: Understand the formation of anhydrides.
Carboxylic acids generally form anhydrides by dehydration, but formic acid is unique in that it does not easily form anhydrides.
Acetic acid, propionic acid, and n-butyric acid readily form anhydrides.
Step 2: Identify the acid that does not form anhydride.
Formic acid does not readily form anhydrides, whereas the other listed acids do.

Step 1: Understand the reducing power of halogen acids.
The reducing power of halogen acids increases as we move down the group in the periodic table.
This is because the bond strength between hydrogen and the halogen decreases as the size of the halogen increases, making it easier for the halogen to donate electrons.
Step 2: Identify the correct order.
The reducing power increases in the order: .

Step 1: Understanding Lewis Acidity
Lewis acids are compounds that accept electron pairs.
The strength of a Lewis acid depends on the ability of the central atom to accept electrons.
The more electronegative the substituent, the stronger the acid.
Step 2: Explanation of the Trend
(boron trifluoride) has the highest electronegativity due to the fluorine atoms, which makes it the strongest Lewis acid.
(boron trichloride) is less electronegative than , making it a weaker acid.

(boron tribromide) has the lowest electronegativity among the three and is thus the weakest Lewis acid.

Step 3: Conclusion
Thus, the correct order of Lewis acid strength is .