state gov MP Forest Guard and Jail Prahari Mock Test 2023 General Science Chemistry Basic Concepts of Chemistry
Identify the correct set of isotones among the following options.
1
\(\rm { }_{\ \ 7}^{15} \mathrm{~N} \ and \ { }_{\ \ 8}^{16} \mathrm{O} \)
2
\(\rm { }_{ \ \ 8}^{16} O \ and \ { }_{\ \ 8}^{18} O\)
3
\(\rm { }_{20}^{40} \mathrm{Ca} \ and \ { }_{19}^{40} {K}\)
4
\(\rm { }_{18}^{40} \mathrm{Ar} \ and \ { }_{19}^{40} \mathrm{K}\)