Question

Why AlF3 is ionic while AlCl3 is covalent?

Answer 1

Answer:

Explanation:f is more electronegative so it shows ionic bond with al, on the other hand cl and other halogens are less electronegative and show polarization, so it forms covalent bond with cl.

Answer 2

AlF3 is an ionic compound whereas AlCl3 is a covalent compound.

• An ionic compound is formed by the bonding of ions through sharing where one ion donates the electrons and the other ion receives the electrons. For Example, NaCl is an ionic compound because Na shares one of its electrons with Cl to complete octet configuration. Hence, NaCL is considered an ionic compound.
• A covalent compound is formed when the mutual sharing of electrons takes place between the atoms. Sharing of one or more than one electrons takes place in covalent compounds. For example, H2O is considered a covalent compound because the electron pairs are being shared for both of the atoms. ( Hydrogen shares its electron with Oxygen).
• A compound can be determined as covalent or ionic by finding the differences in electronegativities of both elements.
• let X be the electronegativity difference of the two elements, the percentage of ionic character is given by the formula,

=>  Percentage of ionic character =  16(X) + 3.5(X^2).

• For the same cation, if the size of anion increases then the ionic character decreases gradually. (  According to properties of bond formation)
• As the size of Chlorine is higher than Fluorine, AlF3 is considered Ionic whereas AlCl3 is considered Covalent.

Therefore, AlCl3 is considered covalent and AlF3 is considered Ionic.