The metal in question is sodium. Normally, it isn’t transparent, but molten sodium hydroxide does turn transparent after it — well, sort of explodes. Of course, sodium hydroxide isn’t really ...

A green precipitate forms when dilute sodium hydroxide solution is added to a sample in solution. Identify the metal ion present in the original solution.

Add 3M or 6M NH4OH drop wise while stirring with the stir rod to one beaker or test tube of each pair. The solutions will become cloudy and change color due to the precipitation of metal hydroxides.

This is because they're very reactive. When a Group 1 element reacts with water it produces a metal hydroxides solution and hydrogen gas. Let's try it with a lithium. So, on with eye protection ...