A cloud forms during the water cycle which of Earth's spheres does this event occur in

Atmosphere

Explanation:

The atmosphere is the sphere of gases. Here, the bulk of all the gases on earth are located.

For a cloud to form, water on the surface of earth must rise in form of vapor. Water vapor is the gaseous from of water. Water can exist in different states of matter such as solid, liquid and gas. When water evaporates, it turns into a gaseous form.

In the atmosphere, water becomes supercooled and condenses onto the surfaces of dust particles. The dust particles serves as nuclei from cooled water droplets to aggregate before they fall as rain or snow.