AP BIOLOGY

Detailed explanation-1: -In tetrachloromethane (CCl4) there is a difference in electronegativities of Carbon and Chlorine (0.5). This means the electrons in each bond are not shared equally but pulled closer to the Chlorine due to its higher electronegativity.

Detailed explanation-2: -Cl (E.N= 3.16) is more electronegative than C (E.N= 2.55). Due to the high electronegativity of Cl, chlorine strongly attracts the shared electron cloud from each C-Cl bond in the CCl4 molecule. There is an electronegativity difference of 3.16 – 2.55 = 0.61 units.

Detailed explanation-3: -Polar Covalent Bonds A bond in which the electronegativity difference between the atoms is between 0.5 and 2.1 is called a polar covalent bond.

Detailed explanation-4: -If it is greater than 2 they are substantially different and more electronegative atom completely removes a valence electron from the electropositive, forming an ionic compound, and if it is between 0.5 and 2.0 it is polar covalent.