Q64E - Chemistry (OpenStax)

Question

Question: Which bond in each of the following pairs of bonds is the strongest? 

(a) \({\rm{C - C}}\) or \({\rm{C = C}}\) 

(b) \({\rm{C - N}}\) or \({\rm{C}} \equiv {\rm{N}}\) 

(c) \({\rm{C}} \equiv {\rm{O}}\) or \({\rm{C = O}}\) 

(d) \({\rm{H - F}}\) or \({\rm{H - Cl}}\) 

(e) \({\rm{C - H}}\) or \({\rm{O - H}}\) 

(f) \({\rm{C - N}}\) or \({\rm{C - O}}\)

Step-by-Step Solution

Answer

(a) \({\rm{C = C}}\) has stronger bond due to multiple bonds between same elements.

(b) \({\rm{C}} \equiv {\rm{N}}\) has stronger bond due to multiple bonds between same elements.

(c) \({\rm{C}} \equiv {\rm{O}}\) has stronger bond due to multiple bonds between same elements.

(d) \({\rm{H - F}}\) has stronger bond due to greater electronegative difference.

(e) \({\rm{O - H}}\) has stronger bond due to greater electronegative difference.

(f) \({\rm{C - O}}\) has stronger bond due to greater electronegative difference.

Step 1: Concept Introduction

Chemical bonding is the creation of a chemical compound by forming a chemical link between two or more atoms, molecules, or ions. The atoms in the resultant molecule are held together by chemical bonds.

Step 2: Strongest bond in \({\rm{C - C}}\) and \({\rm{C = C}}\)

A multiple bond between two same elements is stronger than single bond.

Therefore \({\rm{C = C}}\) is stronger than \({\rm{C - C}}\).

Step 3: Strongest bond in \({\rm{C - N}}\) and \({\rm{C}} \equiv {\rm{N}}\)

(b)

A multiple bond between two same elements is stronger than single bond.

Therefore \({\rm{C}} \equiv {\rm{N}}\)is stronger than \({\rm{C - N}}\).

Step 4: Strongest bond in \({\rm{C}} \equiv {\rm{O}}\) and \({\rm{C = O}}\)

(c)

A multiple bond between two same elements is stronger than single bond.

Therefore \({\rm{C}} \equiv {\rm{O}}\)is stronger than \({\rm{C = O}}\).

Step 5: Strongest bond in \({\rm{H - F}}\) and \({\rm{H - Cl}}\)

(d)

The greater the electronegativity difference between two similar elements, the stronger is the bond. The electronegativity increases from left to right and from bottom to up in a periodic table.

Therefore, bond between \({\rm{H - F}}\) is stronger than \({\rm{H - Cl}}\).

Step 6: Strongest bond in \({\rm{C - H}}\) and \({\rm{O - H}}\)

(e)

The greater the electronegativity difference between two similar elements, the stronger is the bond. The electronegativity increases from left to right and from bottom to up in a periodic table.

Therefore, bond between \({\rm{O - H}}\) is stronger than \({\rm{C - H}}\).

Step 7: Strongest bond in \({\rm{C - N}}\) and \({\rm{C - O}}\)

(f)

The greater the electronegativity difference between two similar elements, the stronger is the bond. The electronegativity increases from left to right and from bottom to up in a periodic table.

Therefore, bond between \({\rm{C - O}}\) is stronger than \({\rm{C - N}}\).