Water in a lake is synthetic or natural materials

Water in a lake is made up of natural materials. It is a naturally occurring compound made up of hydrogen and oxygen molecules.

Water in a lake is a natural material. It is sourced from rainfall, snowmelt, groundwater, and surface runoff. Lakes form naturally as a result of geological processes, such as the movement of glaciers, volcanic activity, or the sinking of land. Synthetic materials refer to manufactured substances, which do not occur naturally.