Question: what is a atom

Melissa Brereton answered on 17 Mar 2013:

Atoms are the building blocks of everything around us- the contain a nucleus which has protons and neutrons, and surrounding the nucleus are electrons which spin around. All the atoms such as sodium, potassium, calcium, gold, silver have different number of protons, neutrons and electrons. And when two atoms combine together like when sodium and chloride mix to make salt, sometime they share the electrons!