Covalent Bonds- 2020

Which of these elements does not exist as a diatomic molecule?

• Ne

• F

• H

• I

How do atoms achieve noble-gas electron configurations in single covalent bonds?

• One atom completely loses two electrons to the other atom in the bond.

• Two atoms share two pairs of electrons.

• Two atoms share two electrons.

• Two atoms share one electron.

Why do atoms share electrons in covalent bonds?

• to become ions and attract each other

• to attain a noble-gas electron configuration

• to become more polar

• to increase their atomic numbers

Which of the following elements can form diatomic molecules held together by triple covalent bonds?

• carbon

• oxygen

• fluorine

• nitrogen

Which elements can form diatomic molecules joined by a single covalent bond?

• hydrogen only

• halogens only

• halogens and members of the oxygen group only

• hydrogen and the halogens only

Which of the following is the name given to the pairs of valence electrons that do not participate in bonding in diatomic oxygen molecules?

• unvalenced pair

• outer pair

• inner pair

• unshared pair

A molecule with a single covalent bond is ____.

• CO₂

• Cl₂

• CO

• N₂

According to VSEPR theory, molecules adjust their shapes to keep which of the following as far apart as possible?

• pairs of valence electrons

• inner shell electrons

• mobile electrons

• the electrons closest to the nuclei

The shape of the methane (CH4) molecule is called ____.

• tetrahedral

• square

• four-cornered

• planar

What causes water molecules to have a bent shape, according to VSEPR theory?

• repulsive forces between unshared pairs of electrons

• interaction between the fixed orbitals of the unshared pairs of oxygen

• ionic attraction and repulsion

• the unusual location of the free electrons