Indicate whether each of the following statements is true or false. For each statement that is false, correct the statement to make it true. (a) Acid strength in a series of \(\mathrm{H}-\mathrm{A}\) molecules increases with increasing size of A. (b) For acids of the same general structure but differing electronegativities of the central atoms, acid strength decreases with increasing electronegativity of the central atom. (c) The strongest acid known is HF because fluorine is the most electronegative element.

Acid strength in a series of H-A molecules increases with increasing size of A. In a series of H-A molecules, as the size of A increases, the bond between H and A weakens. As a result, the acid strength increases. Therefore, this statement is true.

For acids of the same general structure but differing electronegativities of the central atoms, acid strength decreases with increasing electronegativity of the central atom. For acids with the same structure, as the electronegativity of the central atom increases, the strength of the bond between the central atom and hydrogen also increases. This leads to a decreased ability of the central atom to donate a proton, hence the acid strength decreases. So this statement is also true.

The strongest acid known is HF because fluorine is the most electronegative element. While it is true that fluorine is the most electronegative element, the strongest acid is not HF. At standard conditions, HCl, HBr, and HI are stronger acids than HF. This is primarily due to the small size of the fluorine atom, which results in a shorter and stronger bond between the hydrogen atom and the fluorine atom, making it more difficult for the HF molecule to dissociate (donate a proton) when compared to other hydrogen-halogen molecules. Thus, this statement is false. To correct the statement, we can say: "Fluorine is the most electronegative element, but HF is not the strongest acid. At standard conditions, HCl, HBr, and HI are stronger acids than HF due in part to the small size of the fluorine atom."