A plot of the number of neutrons versus protons for stable isotopes forms a specific "belt of stabil — Nuclear Chemistry and Radioactivity Chemistry Question

💡 Solution & Explanation

For elements with low atomic numbers ($Z < 20$), the stable $n/p$ ratio is $1$. As $Z$ increases, repulsive forces between protons require proportionally more neutrons to maintain stability, causing the $n/p$ ratio to gradually increase up to roughly $1.52$ for the heaviest stable elements. Elements beyond this limit (specifically with $Z \ge 84$) fall outside the stability zone and undergo spontaneous radioactive decay.