What will form when metals dissolve in water?

When metals dissolve in water, they often react to form metal hydroxides. This occurs especially with alkali and alkaline earth metals, such as sodium, potassium, and calcium. When these metals react with water, they displace hydrogen and form hydroxides while also releasing hydrogen gas.

The formation of metal hydroxides can be understood through the general reaction where a metal (M) reacts with water (H2O); it releases hydroxide ions (OH-) and produces a corresponding metal hydroxide (MOH). For instance, when sodium reacts with water, it forms sodium hydroxide (NaOH) and hydrogen gas (H2), which is often observed as bubbling.

The concept reinforces that metals not only dissolve but also engage in chemical reactions that produce new compounds, specifically metal hydroxides, in aqueous solutions. This property is characteristic of certain metals in the periodic table that readily react with water.