Multiple Choice Test: Bonding and Ionic Compounds

What holds the electrons in the outer shells of atoms together?

• Neutrons

• Protons

• Electrons

• Valence electrons

Answer explanation

Valence electrons are the outermost electrons in an atom and are responsible for chemical bonding. They hold the electrons in the outer shells together, allowing atoms to interact and form compounds.

Why are filled electron shells stable?

• They have equal numbers of protons and neutrons

• They have the maximum number of electrons

• They have no protons

• They can form covalent bonds

Answer explanation

Filled electron shells are stable because they contain the maximum number of electrons allowed for that shell, leading to a lower energy state and greater stability. This is why the correct answer is 'They have the maximum number of electrons'.

How many electrons does the 1st electron shell hold?

• 2

• 4

• 6

• 8

Answer explanation

The 1st electron shell, also known as the K shell, can hold a maximum of 2 electrons. This is determined by the formula 2n², where n is the shell level (n=1 for the 1st shell). Therefore, the correct answer is 2.

How many electrons does the 2nd electron shell hold?

• 2

• 4

• 8

• 10

Answer explanation

The 2nd electron shell can hold a maximum of 8 electrons, following the formula 2n², where n is the shell level. For n=2, 2(2)² = 8, making 8 the correct answer.

How many electrons does the 3rd electron shell hold?

• 2

• 6

• 8

• 12

Answer explanation

The 3rd electron shell can hold a maximum of 8 electrons, following the formula 2n², where n is the shell number. For n=3, 2(3)² = 18, but the 3rd shell can only accommodate 8 electrons in practice.

Which type of bond occurs between metal and non-metal atoms?

• Covalent

• Ionic

• Metallic

• Hydrogen

Answer explanation

Ionic bonds form between metal and non-metal atoms when electrons are transferred from the metal to the non-metal, creating charged ions that attract each other. This is distinct from covalent, metallic, and hydrogen bonds.

Which type of bond involves sharing electrons between nonmetals?

• Ionic

• Covalent

• Metallic

• Van der Waals

Answer explanation

Covalent bonds involve the sharing of electrons between nonmetals, allowing them to achieve stable electron configurations. In contrast, ionic bonds involve the transfer of electrons, and metallic bonds involve a sea of delocalized electrons.

Which type of bond occurs between metal atoms only?

• Ionic

• Covalent

• Metallic

• Hydrogen

Answer explanation

Metallic bonds occur between metal atoms, allowing them to share electrons freely, which gives metals their characteristic properties like conductivity and malleability. Ionic bonds involve metals and nonmetals, while covalent bonds are between nonmetals.

What happens to atoms with incomplete outer electron shells?

• They remain stable

• They form bonds to become stable

• They lose protons

• They gain neutrons

Answer explanation

Atoms with incomplete outer electron shells are unstable. To achieve stability, they form bonds with other atoms by sharing, gaining, or losing electrons, thus completing their outer shells.

What is an ion?

• An atom with no charge

• An atom with equal protons and electrons

• An atom with an electrical charge

• An atom that cannot form bonds

Answer explanation

An ion is defined as an atom that has gained or lost one or more electrons, resulting in an electrical charge. Therefore, the correct answer is 'An atom with an electrical charge', as it accurately describes an ion.