List the following bonds in order of increasing ionic character: potassium to iodine, carbon to oxygen, lithium to fluorine, boron to fluorine. (Enter the two elements of the bond into the appropriate box: KI, CO, LiF, BF)

CO < BF < KI < LiF

Explanation:

The magnitude of ionic character in a bond is dependent on the magnitude of electronegativity difference between the atoms in the bond.

Remember that no bond is 100% ionic or covalent according to Linus Pauling. However, the percentage ionic character depends on electronegativity difference between the bonding atoms and polarizability (Fajan's rules).

Between LiF and KI, Fajan's rules become very important. The Li^+ is small and highly polarizing.  The stronger the polarising power of the cation and the higher the polarisability of the anion the more covalent character is expected in a bond

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

answer: a tank of height h is filled with water and sits on the ground. water squirts from a hole at a height y above the ground and has a range r. for two y values, 0 and h, r is zero. determine the value of y for which the range will be a maximum.

explanation: