According to the Group Displacement Law (Rutherford-Soddy rules), specific shifts occur in the perio — Nuclear Chemistry and Radioactivity Chemistry Question

💡 Solution & Explanation

Option A is correct: $\alpha$ -decay drops A by 4 and Z by 2, maintaining the $(A-2Z)$ isotopic number, creating an isodiaphere. Option B is correct: $\beta^-$ -decay leaves mass $A$ unchanged but increases $Z$ by 1, creating an isobar one group to the right. Option C is correct: $1\alpha$ drops Z by 2, $2\beta^-$ raise Z by 2, returning to the parent Z and forming an isotope. Option D is incorrect; a neutron carries no charge ($Z=0$), so its emission changes the mass number (forming an isotope) but does not shift the element's group in the periodic table.