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any tips on learning shapes of molecules and bond angles?

Theres 12 individual shapes I need to learn so I just wanted to know if there was anything I should know about.
Very tough topic to learn, I recommend a chart with the columns being the shape, bond angle, lone pair etc.
Reply 2
Know what the shape names actually mean - e.g. trigonal planar is just a triangle of electron pairs across a plane
Original post by Da14a
Know what the shape names actually mean - e.g. trigonal planar is just a triangle of electron pairs across a plane


Original post by Native087
Very tough topic to learn, I recommend a chart with the columns being the shape, bond angle, lone pair etc.

Do you guys believe that I should just try and memorize them then?
Original post by Helpstudent402
Do you guys believe that I should just try and memorize them then?

Yes, they are relatively big parts on the exam. Normally there is a section dedicated solely to that topic, and then some marks scattered throughout based on shapes or bond angles.
Reply 5
Original post by Helpstudent402
Do you guys believe that I should just try and memorize them then?

Yes they are free marks if you memorize them.
Original post by Helpstudent402
Theres 12 individual shapes I need to learn so I just wanted to know if there was anything I should know about.

Hi! :hi:

This is how I learnt them:

1. Make a chart
When I first learnt the shapes of molecules, I made a chart with columns (Name, Pairs of electrons, Bond angle, Example etc). I then filled them in with each column being a different colour.

2. Learn them
This is the boring bit but it's a great feeling once you've memorised them. I did this step on a whiteboard but scrap paper will do. I looked at the chart I had made and tried to memorise by associating what I already knew. For example, a linear molecule reminded me of a line which is straight, so therefore it will be 180 degrees.
I made another table on a whiteboard and filled it as best as I could without looking. Then I looked back at my chart after and filled in the parts I couldn't remember in a different colour. The different colours made it easier for me to remember what I had missed out which I consequently remembered when I tried again!

3. Questions
Learning the shapes of molecules is great and all but you can still lose marks if you don't know how to identify a molecule's shape. Physics and Maths Tutor is great for questions: https://www.physicsandmathstutor.com/

The best thing to do is go over your shapes of molecules frequently so you don't forget them! They crop up somehow in tests and the more practice you do, the easier it will become.

I hope this helped.
Original post by 5hyl33n
Hi! :hi:

This is how I learnt them:

1. Make a chart
When I first learnt the shapes of molecules, I made a chart with columns (Name, Pairs of electrons, Bond angle, Example etc). I then filled them in with each column being a different colour.

2. Learn them
This is the boring bit but it's a great feeling once you've memorised them. I did this step on a whiteboard but scrap paper will do. I looked at the chart I had made and tried to memorise by associating what I already knew. For example, a linear molecule reminded me of a line which is straight, so therefore it will be 180 degrees.
I made another table on a whiteboard and filled it as best as I could without looking. Then I looked back at my chart after and filled in the parts I couldn't remember in a different colour. The different colours made it easier for me to remember what I had missed out which I consequently remembered when I tried again!

3. Questions
Learning the shapes of molecules is great and all but you can still lose marks if you don't know how to identify a molecule's shape. Physics and Maths Tutor is great for questions: https://www.physicsandmathstutor.com/

The best thing to do is go over your shapes of molecules frequently so you don't forget them! They crop up somehow in tests and the more practice you do, the easier it will become.

I hope this helped.


Original post by Da14a
Yes they are free marks if you memorize them.


Original post by Native087
Yes, they are relatively big parts on the exam. Normally there is a section dedicated solely to that topic, and then some marks scattered throughout based on shapes or bond angles.

Alright, thanks guys, I shall try to take your advice on board!
Original post by Helpstudent402
Do you guys believe that I should just try and memorize them then?


Here's an online test to help you:

www.ibchem.com/test/htm/shapes_hl.htm

You will need to activate flash in your computer browser.

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