JEE Advanced levelSingle correct optionDifficulty 3 of 3bn211
Assertion (A): The average oxidation number of S in SX2OX3X2− is +2.
Reason (R): Both S atoms in thiosulfate have the same oxidation number of +2.
Choose the correct option.
ABoth A and R are true and R is the correct explanation of A
BBoth A and R are true but R is not the correct explanation of A
CA is true but R is false
DA is false but R is true
Answer: C
2x+3(−2)=−2 gives average x=+2 (A true). In thiosulfate one S is bonded to three O and the other (terminal S bonded only to S) behaves like sulfide, so they are +6 and −2, not equal (R false).