Chemistry help - molecules and particles

Watch
spurs9393
Badges: 13
Rep:
?
#1
Report Thread starter 6 years ago
#1
Hi, Im currently revising GCSE Chemistry and I've noticed that, when describing reactions, sometimes we use the word "molecule" whereas sometimes we call them "particles", eg CO2 is a molecule but Fe2O3 is a particle. What is the difference between them and when do we use one as opposed to the other?

Thanks
0
reply
Chlorophile
  • Study Helper
Badges: 20
Rep:
?
#2
Report 6 years ago
#2
(Original post by spurs9393)
Hi, Im currently revising GCSE Chemistry and I've noticed that, when describing reactions, sometimes we use the word "molecule" whereas sometimes we call them "particles", eg CO2 is a molecule but Fe2O3 is a particle. What is the difference between them and when do we use one as opposed to the other?

Thanks
A molecule is an electrically neutral group of atoms held together by covalent bonds. So, for instance, CO2 is a molecule since it only has covalent bonds but Fe2O3 isn't since its bonding is (sort of) ionic. So it's technically incorrect to call a group of atoms a molecule when there's ionic or metallic bonding.

A particle is just a name given to something very small to be used in a model. Chemically, it's not a particularly brilliant word to use but it's used a lot in things like kinetic theory to describe the motion of gasses, etc. A particle could in theory be anything as long as it's made of discrete bits.

In general, I wouldn't use the world particle unless the actual nature of those particles is less important, for instance in kinetic theory.
0
reply
X

Quick Reply

Attached files
Write a reply...
Reply
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Should there be a new university admissions system that ditches predicted grades?

No, I think predicted grades should still be used to make offers (688)
33.87%
Yes, I like the idea of applying to uni after I received my grades (PQA) (863)
42.49%
Yes, I like the idea of receiving offers only after I receive my grades (PQO) (389)
19.15%
I think there is a better option than the ones suggested (let us know in the thread!) (91)
4.48%

Watched Threads

View All