Fully protonated glycine can be purchased as a white crystalline solid. Because it has a net charge of 1 the crystals must contain a compensating negatively charged ion. If a 0.1 M solutions of glycine were to be prepared, the approximate concentration of gly 1 would be

In the same way that a large solid holds its shape, the atoms inside of a solid are not allowed to move around too much. Atoms and molecules in liquids and gases are bouncing and floating around, free to move where they want. The molecules in a solid are stuck in a specific structure or arrangement of atoms.