An atom is smallest particle there is and it cannot be broken down any more.
All of the elements of the Periodic Table cannot be broken down into simpler substances.
If an unknown substance cannot be broken down into simpler substances it is made of one kind of atom and an element.
This is an atom.
I think your referring to an element, the basic unit(s) that cannot be broken down without fission.
A substance that cannot be broken down (science)
A substance that cannot be broken down any further and stays the same substance would be an element
An element cannot be broken down into a simpler substance by chemical means.
A pure substance that cannot be broken down is an Element.
A substance that cannot be broken down is a pure substance
An element is the only substance that cannot be broken down.
an element is a substance that cannot be broken down into a simpler form by chemical means
This question is misguided. A property is not a concrete thing so it is incorrect to speak of breaking it down. (It means something you can say about a substance or an object.) I suspect you mean what type of substance cannot be broken down any further, and the answer to that is an element. It is a property of an element that it cannot be broken down even by chemical changes.
An Element ... A substance that cannot be broken down into simpler substances by chemical means.
T=It is true that compounds is a type of substance. This substance cannot be broken down.
All of the elements of the Periodic Table cannot be broken down into simpler substances.
No. Elements cannot be broken down into simpler substances in a chemical reaction.
No, it can be broken down.