Question

3. Consider the four compounds CH, NHs, H,O, and HF. Use periodic trends in bond lengths and the electronegativity table in Chang to answer the following questions: (a) Which molecule is expected to have the longest bonds? (b) Which molecule is expected to have the most polar bonds? (c) Which molecule is expected to have the least polar bonds? 4. Atom hybridization changes in many chemical reactions. In each of the following reactions determine what change, if any, occurs to the hybridization of the underlined atom. (a) HN NH+H2 H2N-NH

Answer 1

ond In Methane . 09 A Pond leng t N-H bond i NHo9R Band.length o-н bond m o o.96A. fo cHy being the ongest bonde b CH is NoN -Polar Morle f o bei] sp brizd and NiH is a leo fp3 Hybridized HF 's sp Hybridized Hy bridliz ed and NH So, HF Mlerule Has Mast pola bonds CHy bemg NoN pola Have lrast Polan bords S P in Reactant HbN-SP im Brooduet Hybof N sp3

BOND DISTANCE IN METHANE CAN BE FIND OUT BY COMPARING THE POLA RITY OF BOND

ALSO AS METHANE IS NON POLAR MOLECULE AND HF WATER AND AMMONIA IS POLAR

BUT HF BEING SP HYBRIDISED BECOME MOST POLAR AND METHANE BEING THE MOST NON POLAR AND METHANE HAS THE HIGHEST BOND TO BOND DISTANCE

CHANGE IN HYBRIDISATION CAN BE MARKED BY TAKING THE HYBRIDISATION OF CENTRAL ATOM