Question
Chemistry Question on Chemical Reactions
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: H2Te is more acidic than H2S.
Reason R: Bond dissociation enthalpy of H2Te is lower than H2S.
In light of the above statements, choose the most appropriate from the options given below:
A is true but R is false.
A is false but R is true.
Both A and R are true but R is NOT the correct explanation of A.
Both A and R are true and R is the correct explanation of A.
Both A and R are true and R is the correct explanation of A.
Solution
Understanding Assertion A: The acidity of hydrogen compounds such as H2S and H2Te can be compared based on the stability of the conjugate base formed after deprotonation. H2Te has a larger atomic size and weaker H–Te bonds compared to H–S, which leads to easier ionization of H2Te and thus higher acidity.
Understanding Reason R: The bond dissociation enthalpy is a measure of the strength of the bond between hydrogen and the other element (S or Te). Since H–Te bonds are weaker than H–S bonds, H2Te dissociates more easily, supporting the assertion that H2Te is more acidic than H2S.
Therefore, the correct interpretation of both statements shows that both Assertion A and Reason R are true, and R indeed provides the correct explanation for A.