Answer is: the atom is the smallest known particle of matter.
John Dalton claimed that atom is indestructible and a<span>ll atoms of a given element are identical in mass and properties.
</span>Thomson discovered electron and found the first evidence for isotopes<span> of a stable element.</span>
<span>The organisms in the soil food chain that don't obtain energy directly from plants are protozoa.
</span>
A physical change has occured, Boiling water is a physical change not a chemical one, now if you're talking about the electric current, that had not changes either. it may rearrange the molecules, but it does not change the fundamental properties of the substance.
