Match the column: Column I (Mode of decay) with Column II (Effect on atomic number and mass number) — Nuclear Chemistry and Radioactivity Chemistry Question

💡 Solution & Explanation

$\alpha$-decay lowers the atomic number by 2 and mass number by 4 (A $\to$ Q, S). $\beta$-decay increases the atomic number by 1 while the mass number remains unchanged (B $\to$ P, T). $\gamma$-decay leaves both atomic and mass numbers unchanged (C $\to$ R, T). Positron decay and K-capture leave the mass number unchanged (D $\to$ T, E $\to$ T). Note: They also decrease atomic number by 1, but this option is not available in Column II. Therefore, correct answer is A-Q, S; B-P, T; C-R, T; D-T; E-T.