Question

List the bonds \(\mathbf{P}-\mathbf{C l}, \mathbf{P}-\mathbf{F}, \mathbf{O}-\mathbf{F},\) and \(\mathbf{S i}-\mathbf{F}\) from least polar to most polar.

Short answer

The order of bond polarity from least polar to most polar is: \( \mathbf{O}-\mathbf{F}, \mathbf{P}-\mathbf{C l}, \mathbf{P}-\mathbf{F}, \mathbf{S i}-\mathbf{F} \).

Step-by-step solution

Calculate electronegativity differences for P-Cl

\( \textrm{Electronegativity difference} = |2.19 - 3.16| = 0.97 \)

Calculate electronegativity differences for P-F

\( \textrm{Electronegativity difference} = |2.19 - 3.98| = 1.79 \)

Calculate electronegativity differences for O-F

\( \textrm{Electronegativity difference} = |3.44 - 3.98| = 0.54 \)

Calculate electronegativity differences for Si-F

\( \textrm{Electronegativity difference} = |1.90 - 3.98| = 2.08 \) We now have the electronegativity differences for each bond: - P-Cl: 0.97 - P-F: 1.79 - O-F: 0.54 - Si-F: 2.08

Arrange the bonds in order of increasing polarity

Based on the electronegativity differences, the bonds can be listed from least polar to most polar as follows: 1. O-F (0.54) 2. P-Cl (0.97) 3. P-F (1.79) 4. Si-F (2.08) So, the order of bond polarity is: \( \mathbf{O}-\mathbf{F}, \mathbf{P}-\mathbf{C l}, \mathbf{P}-\mathbf{F}, \mathbf{S i}-\mathbf{F} \)

Key concepts

Chemical Bond Polarity

Diving into the world of chemical bonds, an important aspect is the concept of polarity. A chemical bond is said to be polar if the two atoms involved exhibit a significant difference in electronegativity. Electronegativity refers to the ability of an atom to attract shared electrons in a chemical bond.

When the difference in electronegativity between two bonded atoms is large, the more electronegative atom will attract the bonding electrons closer to itself. This unequal sharing of electrons leads to a partial negative charge on the more electronegative atom and a partial positive charge on the less electronegative one, giving rise to what is known as a dipole moment.

The greater the electronegativity difference, the more polar a bond will be. Let's use what we know to enhance the learning experience here: when comparing the bonds P-Cl, P-F, O-F, and Si-F, it is the Si-F bond that has the largest electronegativity difference of 2.08, making it the most polar. Conversely, the O-F bond has the smallest difference, and thus, it is the least polar among the ones listed.

Chemical Bonding

Chemical bonding is a fundamental concept in chemistry that describes the force holding atoms together to form molecules and compounds. There are several types of chemical bonds, each with unique characteristics, including ionic bonds, covalent bonds, and metallic bonds.

In ionic bonding, atoms transfer electrons to achieve stable electron configurations, typically occurring between metals and nonmetals. Meanwhile, covalent bonding involves the sharing of electron pairs between atoms, with the shared electrons holding the atoms together, typically found between nonmetals. Lastly, metallic bonding is characterized by a 'sea' of delocalized electrons shared among a lattice of metal ions.

When assessing bond polarity, we're primarily looking at covalent bonds, where the difference in electronegativity can lead to unequal electron sharing. This knowledge can be applied in our approach, where the electronegativity differences give us a clear picture of how polar the covalent bonds are, guiding us to deeper understanding.

Periodic Trends

The periodic table is not just a collection of elements, but a map of chemical and physical trends. One of these trends is electronegativity, which generally increases across a period (from left to right) and decreases down a group (from top to bottom).

Understanding this trend can help us predict the bond polarity of different bonds just as we did in our example. For instance, fluorine, being the most electronegative element on the periodic table, forms highly polar bonds with other atoms.

When looking at electronegativity differences to determine bond polarities, we're integrating the concept of periodic trends into our analysis. This allows us to see why, for example, a bond involving silicon (left of fluorine in the same period) and fluorine will be more polar due to the more pronounced difference in electronegativity, following the trends presented in the periodic table.