Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): 10 g of O ₂ gas contains more molecules than 10 g of O ₃ gas, but both samples contain the same total number of oxygen atoms. Reason (R): For a given mass of allotropes, the number of molecules is inversely proportional to the molar mass, but the total number of atoms depends only on the given mass

Step-by-step solution

Assertion (A) is true: Number of molecules = Given mass Molar mass N_A . For 10 g of O ₂ , molecules = 10 32 N_A . For 10 g of O ₃ , molecules = 10 48 N_A . Thus, O ₂ has more molecules. The number of atoms in O ₂ = 10 32 2 N_A = 10 16 N_A . The number of atoms in O ₃ = 10 48 3 N_A = 10 16 N_A . Both contain the same number of atoms. Reason (R) is true and explains (A): For a given mass w of an allotrope with atomicity x and atomic mass M_a , the molar mass is x M_a . The number of molecules is w x M_a N_A , which