The Student Room Group

Electrolysis Problem

Well, just running through some stuff, and I'm at a lost for one thing, it's part of a electrolysis question.

1) When the heat source was removed the crucible cooled and the lamp when out. Explain why the lamp went out when the curcible cooled. There is fuse sodium bromide in the crucible.

Is it that the reaction stops taking place between in the electrolyte?

Also at the end of the reaction the crucible was washed out with water, a gas game off, what was this gas?

- Dexnell
Dexnell
Well, just running through some stuff, and I'm at a lost for one thing, it's part of a electrolysis question.

1) When the heat source was removed the crucible cooled and the lamp when out. Explain why the lamp went out when the curcible cooled. There is fuse sodium bromide in the crucible.

Is it that the reaction stops taking place between in the electrolyte?


electrolysis can only happen if the ions are free to move.

either molten or in aqueous solution = free to move

Also at the end of the reaction the crucible was washed out with water, a gas game off, what was this gas?

- Dexnell


you are electrolysing molten sodium bromide - you will make sodium at the cathode. When you add water to this hydrogen gas is made
2Na + 2H2O --> 2NaOH + H2
Reply 2
So the lamp comes out because the ions are no longer free to move, due to the removal of the heat source.


Thanks/