Hi!
The list of properties we need for this standard here on StudyIt does not include brittleness, but it was mentioned in 2019 for ionic compounds - do we need to know this?
Just in case we need it, I was wondering which substances are brittle and which are not, and why?
Thank you!
Hey TheSquishyPigeon (love your name ;-))
When your read the standard found here: https://www.nzqa.govt.nz/nqfdocs/ncea-resource/achievements/2019/as91164.pdf look at Number 5 on page two - you will see that brittleness is not included. But yes you are right it was in the 2019 exam.
In terms of the fundamental knowledge you need just remember that the particles making up the ionic solid are positive and negative ions. If they get knocked and misaligned then the solid will cleave and be brittle.
So to answer your question - ionic solids are brittle. They are the solids that form between metals and non metals.
Hope that helps 