Question

Questions:

For each of the following molecules, draw the Lewis Dot Structure, identify the electronic and molecular geometry names, and predict the bond angle of the bold atom. If you believe that resonance structures exist, you may merely state so.

CH₃I

SO₃

CH₃COOCH₃

PCl₃

ZnCl₂

ZnCl₄^2-

COHC₆H₄COOH

NH₄⁺

ICl₄^-

RnF₂

HArF

B₂H₆ (yes, this is a real molecule)

For what electronic geometries is the “octet rule” always violated?

Though the octet rule is, indeed, frequently broken, it is never broken for small atoms (n = 1, 2). Propose a reason for this. Your answer is extra cool if it included a mention of the Pauli Principle.

Answer 1

Here are lewis structure for the first 4

For the first one it has 4 bonds and it has no lone pair attached to the central atom so

electronic geometry will be tetrahedral , molecular geometry will be tetrahedral too , bond angle will be 109.5 degrees

for SO3, it has 3 bonds and 0 lone pairs of electrons attached to S, electronic geometry will be trigonal

molecular geometry will be trigonal planar with a bond angle of 120 degrees

The CH3COOCH3, for this we need to take a look to the central atoms, it has 4 central atoms

the firs central atom will be the first carbon

electron geometry will be tetrahedral , also molecular geometry will be tetrahedral with angle of 109.5 degrees

second central atom will be the second carbon

it has no lone pairs and has 3 bonds

electron geometry will be trigonal and molecular shape will be trigonal planar with angle of 120 degrees

third central atom will be the oxygen that has no double bond

it has 2 bonds and 2 lone pairs

molecular geometry will be bent

electron geometry will be tetrahedral

bond angle will be 109.5 or less than that

4th central atom will be the last carbon attached to 3 hydrogens and the oxygen

no lone pairs so molecular geometry will be tetrahedral and electron geometry will be tetrahedral

The PCl₃

It has 1 lone pair of electrons and 3 bonds so

electron geometry will be tetrahedral

molecule geometry will be trygonal pyramidal

angle bond will be 109.5 C