In which of the following compounds the electronegativity of phosphorus is greater than that in PCl3?A PH3. B PCl2F. C PF3. D PCl5

To determine in which compound the electronegativity of phosphorus is greater than that in phosphorus trichloride (PCl3), we need to consider the nature of the bonds formed in each compound and how they affect the effective electronegativity of phosphorus. Electronegativity is a measure of an atom's ability to attract electrons in a bond, and it can be influenced by the surrounding atoms.

Analyzing the Compounds

Let's break down each option to see how phosphorus interacts with other elements in these compounds:

• PH3 (Phosphine): In this molecule, phosphorus is bonded to three hydrogen atoms. Hydrogen has a lower electronegativity compared to chlorine, which means that the phosphorus atom does not have to compete with a highly electronegative atom for electron density. This results in a relatively lower effective electronegativity for phosphorus in PH3 compared to PCl3.
• PCl2F (Phosphorus Dichloride Fluoride): Here, phosphorus is bonded to two chlorine atoms and one fluorine atom. Fluorine is the most electronegative element, which pulls electron density away from phosphorus. This could potentially lower the effective electronegativity of phosphorus compared to PCl3.
• PF3 (Phosphorus Trifluoride): In PF3, phosphorus is bonded to three fluorine atoms. Since fluorine is highly electronegative, it significantly pulls electron density away from phosphorus, making the effective electronegativity of phosphorus in PF3 greater than in PCl3.
• PCl5 (Phosphorus Pentachloride): In this compound, phosphorus is surrounded by five chlorine atoms. The presence of multiple electronegative chlorine atoms can also reduce the effective electronegativity of phosphorus compared to PCl3.

Comparative Electronegativity

Now, let's summarize the findings:

• In PH3, phosphorus has a lower effective electronegativity than in PCl3.
• PCl2F has a mixed effect due to the presence of fluorine, but it is likely still lower than PCl3.
• PF3 shows a higher effective electronegativity for phosphorus due to the strong electronegative influence of fluorine.
• PCl5 also results in a lower effective electronegativity due to the high number of electronegative chlorine atoms.

Final Thoughts

Based on this analysis, the compound where the electronegativity of phosphorus is greater than that in PCl3 is PF3. The strong electronegative nature of fluorine significantly influences the phosphorus atom, leading to a higher effective electronegativity in this compound compared to PCl3.