Answer: Atom IV
Step-by-step explanation:
Atoms that have the same number of valence electrons (belong to the same group of the periodic table) have similar properties. Hydrogen and Helium are exceptions. The first shell is filled with 2 electrons which makes Helium a Noble Gas and Hydrogen is a gas thus not a Group 1 metal.
The given atom has 2 valence electrons (a group 2 element).
∴ the atoms with similar properties to that of the given atom would also have 2 valence electrons:
I - filled 1st shell thus noble gas ❌
II - 3 valence electrons ❌
III - 4 valence electrons ❌
IV - 2 valence electrons ✅
∴ atom IV has similar properties to the given atom.
Checking my answer:
If we check the periodic table, the atom given is Be (Alkali Earth Metal)
I is He (Noble Gas)
II is Bo (Group 13)
III is C (Group 14)
IV is Magnesium (Alkali Earth Metal)