Problem 97 - Chemistry: The Central Science

Question

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) In general, the acidity of binary acids increases from left to right in a given row of the periodic table. (b) In a series of acids that have the same central atom, acid strength increases with the number of hydrogen atoms bonded to the central atom. (c) Hydrotelluric acid \(\left(\mathrm{H}_{2} \mathrm{Te}\right)\) is a stronger acid than \(\mathrm{H}_{2} \mathrm{~S}\) because Te is more electronegative than \(\mathrm{S}\).

Step-by-Step Solution

Answer

(a) True. Acidity of binary acids increases from left to right in a given row of the periodic table due to increasing electronegativity. (b) False. Acid strength depends on the stability of the conjugate base of the acid, influenced by factors such as electronegativity and size of the central atom. (c) False. H2Te is a stronger acid than H2S because Te is larger than S, making the H-Te bond weaker and easier to release the proton (H+), not because Te is more electronegative than S.

Step 1: Statement (a)

In general, the acidity of binary acids increases from left to right in a given row of the periodic table. This statement is true. As we move from left to right across a period in the periodic table, the electronegativity of the elements increases. The more electronegative an atom bonded to hydrogen is, the more acidic the binary acid will be, as it will result in a weaker bond with hydrogen, making it easier for the proton (H+) to be released into the solution. #Statement (b) Analysis and Answer#

Step 2: Statement (b)

In a series of acids that have the same central atom, acid strength increases with the number of hydrogen atoms bonded to the central atom. This statement is false. The acid strength depends on the stability of the conjugate base of the acid, not the number of hydrogen atoms bonded to the central atom. The more stable the conjugate base, the stronger the acid. In general, acid strength increases with electronegativity and size of the central atom. Correction: In a series of acids that have the same central atom, acid strength depends on the stability of the conjugate base of the acid, which is influenced by factors such as electronegativity and size of the central atom. #Statement (c) Analysis and Answer#

Step 3: Statement (c)

Hydrotelluric acid \(\left(\mathrm{H}_{2} \mathrm{Te}\right)\) is a stronger acid than \(\mathrm{H}_{2} \mathrm{~S}\) because Te is more electronegative than \(\mathrm{S}\). This statement is false. Although it is true that hydrotelluric acid (H2Te) is a stronger acid than hydrogen sulfide (H2S), it is not because Te is more electronegative than S. Actually, S is more electronegative than Te. The reason why H2Te is a stronger acid than H2S is because Te is much larger than S, making the H-Te bond weaker and more easily broken to release the proton (H+) into the solution. Correction: Hydrotelluric acid \(\left(\mathrm{H}_{2} \mathrm{Te}\right)\) is a stronger acid than \(\mathrm{H}_{2} \mathrm{~S}\) because Te is a larger atom than \(\mathrm{S}\), which makes the H-Te bond weaker and easier to release the proton (H+).