Answer:
The characteristics are as follows:
-It is microscopic.
-It contains three sub atomic particles namely: electrons, protons and neutrons.
-It is the smallest unit of any substance (except for living bodies since smallest unit of them is cell).
-When seen from microscope atoms appear to be blur, spheres.
-They form ions(by losing or gaining electrons) and molecules(by combining with itself or other atoms).
Hope this helps :)
