I need help with question #3. Build 3D models of the fallawing molecules to answ
ID: 1082332 • Letter: I
Question
I need help with question #3.
Build 3D models of the fallawing molecules to answer these questions 1. Circle all of the following malecules that are Wnear H 2. Fill in the table below CO, # of lone pain oncentral Bond Angle bent Dent 3. These molecules each have three atoms, but their bond angles vary. is there a correlation between the number of lone pairs on the central atom and the bond angle for the molecule? Explain. 4. Given the number of lone electrons on the oxygen in Os, estimate the band angle B. Lewis Structures, Molecular Geometry, and Polarity For each of the following examples, . Draw the Lewis structure in the box (including resonance structures when they apply) .Use the Molecular Model kit to make a model . Sketch the 3-dimensional shape of the moleculefion in the box (label bond angies) · Label the molecular geometry (or shape) and list the bond angle(s) presentExplanation / Answer
Loan Pair electrons tend to decrease the bond angle due to repulsion.
Here for H2O molecule the oxygen atom is sp3 hybridized, so the expected bond angle is tetrahedral bond angle i.e. 109º. But the oxygen atom has 2 loan pair electrons. This lone pair-lone pair and lone pair-bond pair repulsion here cause a decrement in bond angle, so the O-H-O bond angle becomes 105º.
For CO2 molecule the carbon atom is sp hybridized, so the expected bond angle is linear bond angle i.e. 180º. The carbon atom has no loan pair electrons, thus no repulsion of electron is observed here, so the O-C-O bond angle remains as same.
Here for NO2- molecule the oxygen atom is sp2 hybridized, so the expected bond angle is trigonal planar bond angle i.e. 120º. NO2- has one extra electron than NO2, so this extra electron remains as non-bonding pair or lone pair electron on nitrogen. This loan pair electron exerts a greater repulsion than the single electron in NO2, therefore the O-N-O angle is reduced to 115.4°.