When a small piece of sodium is placed in a petri dish with water and phenolphthalein, the sodium becomes a molten ball and darts around the dish, leaving a pink trail. The reactions of potassium, ...

When the alkali metals are cut, they initially appear shiny grey but quickly become dull and white as they react with oxygen in the air. This is known as tarnishing. Sodium tarnishes more quickly ...

When the alkali metals react with the different halogens (Group 7 of the periodic table), the group of compounds formed are known as the alkali metals halides. Due to the fact that there are a ...