Question

The bonding of chlorine with each of the Period 3 elements shows a change in bonding type from ionic through polar covalent to nonpolar covalent. Select the properties that reflect this change in bonding character.

Multiple select question.
a. Electrical conductivity at the melting point is high only for chlorides of Group 1A(1) and Group 2A(2).
b. There is a general decrease in ΔEN moving from left to right across the period.
c. Electron density relief maps show a steady increase in electron sharing from NaCl to Cl₂.

Answer 1

The change in bonding character from ionic in Group 1A(1) and Group 2A(2) chlorides to covalent as we move across Period 3 is reflected in properties such as electrical conductivity, electronegativity differences, and electron density relief maps.

Step-by-step explanation:

The student asks about the change in bonding character when chlorine bonds with each of the Period 3 elements. Let's address their proposed properties reflecting this change:

• Electrical conductivity at the melting point is a characteristic that can indicate the type of bonding; ionic compounds typically conduct electricity when melted due to the presence of free ions, hence this property is observed with chlorides that are ionic such as those formed with Group 1A(1) and Group 2A(2) elements.
• There is indeed a general decrease in electronegativity difference (ΔEN) across Period 3 as we move from left to right, which correlates with a decrease in ionic character and an increase in covalent character of the bonds.
• The statement about electron density relief maps is true; as we move from ionic compounds like NaCl to more covalent compounds like Cl₂, there is an increase in electron sharing.

The student's observations about changes in bonding character across Period 3 are supported by trends in properties such as electrical conductivity, changes in ΔEN, and electron distribution in molecules.