Question

Which statement correctly compares an atom of an alkali metal with an atom of the alkaline earth metal next to it on the periodic table?
The alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion.
The alkali metal atom forms a +2 ion, while the alkaline earth metal atom forms a +1 ion.
The alkali metal atom has one less shell of electrons than the atom of the alkaline earth metal.
The alkali metal atom has one more shell of electrons than the atom of the alkaline earth metal.

Answer 1

"The alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion" is the one statement among the choices given in the question that correctly compares an atom of an alkali metal with an atom of the alkaline earth metal next to it on the periodic table. The correct option among all the options is first option.

Answer 2

Answer: The alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion.

Explanation: Group 1 elements are called as alkali metals and group 2 elements are called as alkaline earth metals.

For example, Li is an alkali metal and Be is an alkaline earth metal.

Lithium(Li) has an atomic number of 3 and the electronic configuration is:

Li: $1s^22s^1$

Thus lithium has to lose 1 electron and acquire 1+ charge to attain nearest noble gas configuration.

$Li^+:1s^2$

Berrylium(Be) has an atomic number of 4 and the electronic configuration is:

Be: $1s^22s^2$

Thus berrylium has to lose 2 electrons and acquire 2+ charge to attain nearest noble gas configuration.

$Be^{2+}:1s^2$