10. Periodic Properties of the Elements

How many valence electrons are present in the ground-state electron configuration of a nitrogen atom?

Why does the number of valence electrons increase as you move across a period in the periodic table?

Which of the following represents the valence electron configuration for a nitrogen atom?

In the electron configuration of nitrogen (atomic number 7), what is the role of the 2s electrons?

Which of the following orbital diagrams correctly represents oxygen having six valence electrons?

How many valence electrons does a calcium (Ca) atom have?

How does the number of valence electrons in an element influence its chemical properties?

How many unpaired electrons are present in a ground-state phosphorus (P) atom?

How many valence electrons are present in a molecule of H2S?

How many valence electrons does the element tin (Sn) have?

How many valence electrons does tellurium (Te) have?

Sulfur has an atomic number of 16. How many valence electrons does sulfur have in its outermost shell?

How many valence electrons does the S^{2-} ion have? (Hint: Write out the electron configuration of S^{2-}.)

Which of the following best describes a valence electron and its importance in chemistry?

Which of the following best defines valence in chemistry?