Molecular Shape

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

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Claudeth Martinez 1D
Posts: 52
Joined: Fri Sep 28, 2018 12:18 am

Molecular Shape

Postby Claudeth Martinez 1D » Sun Nov 11, 2018 10:06 pm


Can someone tell me what type of interactions are the dashed lines mean when drawing out the molecule?


Anna O 2C
Posts: 98
Joined: Fri Sep 28, 2018 12:19 am

Re: Molecular Shape

Postby Anna O 2C » Sun Nov 11, 2018 10:34 pm

The dashed lines means that there is an attraction between those two dipole moments. For example, if you draw multiple H2O molecules the dashed lines will be connecting oxygen and hydrogen atoms on the two different molecules because one has a positive and one has a negative dipole so they are attracted to each other.

Alicia Gibbons 1B
Posts: 31
Joined: Fri Sep 28, 2018 12:17 am

Re: Molecular Shape

Postby Alicia Gibbons 1B » Mon Nov 12, 2018 3:55 pm

Keep in mind that dashed lines are intermolecular interactions. Intermolecular interactions can have huge effects: consider hydrogen bonding in water that gives it surface tension. But, intermolecular interactions can also have tiny effects: van der waals forces only occur sporadically and are broken easily. Both could be represented by dashed lines.

Avery Zuelch 1D
Posts: 31
Joined: Fri Sep 28, 2018 12:18 am

Re: Molecular Shape

Postby Avery Zuelch 1D » Mon Nov 12, 2018 4:53 pm

I'm still a bit lost.. What's the difference between dotted lines and a solid line? I thought that they were both notations for interactions?

Christine Chow 4G
Posts: 43
Joined: Fri Sep 28, 2018 12:28 am

Re: Molecular Shape

Postby Christine Chow 4G » Mon Nov 12, 2018 4:59 pm

A solid line means the atoms share and intramolecular bond (and are bonded together to make up a molecule or compound). Dashed lines represent interactions/intermolecular forces between these molecules or compounds.

Cody Do 2F
Posts: 62
Joined: Fri Sep 28, 2018 12:23 am

Re: Molecular Shape

Postby Cody Do 2F » Mon Nov 12, 2018 5:01 pm

Hey Avery!

Both the dotted and solid lines are notations for interactions! A solid line represents a covalent bond between two elements, a type of interaction in which the elements share electrons. A dotted line, however, represents interactions between two molecules (not elements!) due to their slight charges (dipoles). In short, solid lines represent covalent bonds, a type of intramolecular interaction that keeps one molecule together (bonds elements into a molecule). A dotted line represents dipole attraction between multiple molecules (the slight negative side of one molecule is attracted to the slight positive of another).

Posts: 104
Joined: Fri Sep 28, 2018 12:19 am

Re: Molecular Shape

Postby inlovewithchemistry » Tue Nov 13, 2018 3:25 pm

We learned about the wedge and dash model in discussion today. The wedge represents the idea that the atom is coming out at you, and the dashes represent the atom falling behind the structure. This model is just a way to interpret the shape in your head.

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