Chemistry

>

GCSE

Process of Electrolysis

Question

Why does aluminium oxide dissolve in molten cryolite?

3 years ago

·

2 Replies

·

4326 views

C

Chester Gorczany


2 Answers

Carola Profile Picture
Carola Verified Sherpa Tutor ✓

Experienced GCSE Science and A level Chemistry tutor with Phd

21 reviews

Cryolite does not dissolve aluminium oxide, but lowers its melting point.

I'm available for 1:1 private online tuition!

Click here to view my profile and arrange a free introduction.
Duncan A Profile Picture
Duncan A Verified Sherpa Tutor ✓

Head of Chemistry. Examiner. Very experienced online tutor.

2 reviews

Mixtures usually have lower melting points than pure substances so a mixture of cryolite and bauxite melts at a lower temperature than either pure substance. The electrolysis process is actually run at temperatures slightly below the melting point of pure cryolite. Nevertheless as bauxite is repeatedly added to the electrolysis cell it is fair to describe the process as aluminium oxide dissolving in molten cryolite. Both are ionic materials so will dissolve in each other as the ions will held together by electrostatic forces, just as in the pure materials.

I'm available for 1:1 private online tuition!

Click here to view my profile and arrange a free introduction.

Think you can help?

More Chemistry GCSE Questions
Sherpa Badge

Need a GCSE Chemistry tutor?

Get started with a free online introductions with an experienced and qualified online tutor on Sherpa.

Find a GCSE Chemistry Tutor