Question

2. Arrange the following in the decreasin
rder of number of shells
ra, Sr, Be, Ca, Mg

1)Ra, Ba, Sr, Ca, Mg, Be
2)Be, Mg, Ca, Sr, Ba, Ra
3)Ca, Mg, Be, Sr, Ra, Ba​

Answer 1

Answer:

2) Be, Mg, Ca, Sr, Ba, Ra