## Textbook 4.21 part d

(Polar molecules, Non-polar molecules, etc.)

Or Fisher 1I
Posts: 35
Joined: Fri Feb 02, 2018 3:00 am

### Textbook 4.21 part d

Hello, during discussion section my TA told us that we do not need to know specific angles for things besides the 6 basic structures if they were all bonded electron pairs. However, the answer to this problem in the solutions manual is 107$^{\circ}$ for the N2H4 molecule. Do we have to be able to write this or can we just say it is less than 109.5$^{\circ}$? Thanks.

Alma Flores 1D
Posts: 64
Joined: Wed Nov 08, 2017 3:01 am

### Re: Textbook 4.21 part d

Dr. Lavelle replied to another student saying to write slightly less than 109.5 since students are not expected to know the exact (experimentally measured) bond angles for individual molecules.

Posts: 30
Joined: Fri Apr 06, 2018 11:03 am

### Re: Textbook 4.21 part d

We only need to know when it is slightly less than 109.5 vs 109.5 because we cannot actually calculate the degree exactly.

SammiOrsini_1B
Posts: 45
Joined: Fri Apr 06, 2018 11:04 am

### Re: Textbook 4.21 part d

For clarification, since a bond angle of 109.5 refers to a tetrahedral, is a bond angle that is slightly less than 109.5 caused by lone pairs on the central atom? Do bond angles decrease due to lone pairs?