These photos show part II of the lab being performed with the sodium carbonate/bicarbonate mixture. The picture to the right is the mass of the empty crucible and lid.

Then, the sodium carbonate/bicarbonate mixture is added to the crucible.

The crucible is heated for about 10 minutes with the lid ajar to allow gases to escape.

After the crucible was allowed to cool for about 10 minutes its mass was determined again.