Which element has two valence electrons? (1 point)

Calcium
Lithium
Chlorine
Neon

The element with two valence electrons is Calcium.

To determine which element has two valence electrons, we need to look at the electron configuration of each element. Valence electrons are the electrons in the outermost energy level of an atom.

Calcium (Ca) has an atomic number of 20, which means it has 20 electrons in total. The electron configuration of calcium is 1s² 2s² 2p⁶ 3s² 3p⁶ 4s². The outermost energy level, which is the fourth energy level (4s²), contains two valence electrons.

Lithium (Li) has an atomic number of 3, which means it has three electrons in total. The electron configuration of lithium is 1s² 2s¹. The outermost energy level, which is the second energy level (2s¹), contains one valence electron.

Chlorine (Cl) has an atomic number of 17, which means it has 17 electrons in total. The electron configuration of chlorine is 1s² 2s² 2p⁶ 3s² 3p⁵. The outermost energy level, which is the third energy level (3s² 3p⁵), contains seven valence electrons.

Neon (Ne) has an atomic number of 10, which means it has 10 electrons in total. The electron configuration of neon is 1s² 2s² 2p⁶. The outermost energy level, which is the second energy level (2s² 2p⁶), contains eight valence electrons.

Based on this information, the element that has two valence electrons is Calcium.

Look in Column II of the periodic table