What are the smallest lava fragments produced by an explosive eruption called?

Tiniest fragments of lava obtained by  explosion is termed as volcanic ash

Explanation:

Tiniest fragments of lava obtained by  explosion is termed as volcanic ash

Volcanic ash is a combination of fragments of stone, mineral and glass released during a volcano eruption. The molecules are quite small— in size fewer than 2 millimeters. The particles which constitutes volcanic ash can actually travel long distance through wind, due to their small size and low density.

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developed countries have tended to improve the environment, while developing countries have tended to damage it.