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? aThe alkali metal atom forms a +1 ion, while the alkaline earth metal atom forms a +2 ion. bThe alkali metal atom forms a +2 ion, while the alkaline earth metal atom forms a +1 ion. cThe alkali metal atom has one less shell of electrons than the atom of the alkaline earth metal. dThe alkali metal atom has one more shell of electrons than the atom of the alkaline earth metal.

Answer 1

Answer:

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

Explanation:

Let's evaluate each answer.

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

This means that the alkali metal atom has to lose 1 valence electron to form a +1 ion while the alkaline earth metal atom has to lose 2 valence electrons to form a +2 ion. This is accurate because alkali metal atoms have 1 valence electron while alkaline earth metal atoms have 2, so the statement is correct.

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

This would mean that the alkali metal atom has to lose 2 valence electrons to form a +2 ion, while the alkaline earth metal has to lose 1 valence electron to form a +1 ion. This is incorrect because alkali metal atoms only have 1 valence electron and will become a +1 ion when losing that electron, while alkaline earth metals have 2 valence electrons and will form a +2 ion upon losing them.

C: The alkali metal atom has one less shell of electrons than the atom of the alkaline earth metal.

This would mean that the alkali metal atom would be located one period higher up than the alkaline earth metal atom. This is untrue, because the question states that the alkali metal atom is located directly next to the alkaline earth metal atom, so they have the same amount of electron shells.

D: The alkali metal atom has one more shell of electrons than the atom of the alkaline earth metal.

This would mean that the alkali metal atom would be located one period lower on the periodic table than the alkaline earth metal atom. Similar to the previous statement, this is untrue because the question states that they are located directly next to each other, or on the same period.

(Also, I just took this quiz and e2020 says it's right.)

Answer 2

The atom of alkaline earth metal has one more proton and one more electron than the alkali metal that is next to it to the left on the periodic table. Then the atomic number of the alkali metal is one unit less than the atomic number of the alkaline earth metal next to it