Elements.
Substances that cannot be chemically broken down into simpler substances are called elements.
An alloy.
substances that cannot be chemically interconverted or broken down into simpler substances and are primary constituents of matter.
That would be an Element.
Robert Boyle
Elements are substances made of identical atoms which cannot be broken down to other substances. Matter is anything that occupies space and has mass.
A pure substance that cannot be broken down into simpler substances by physical or chemical means is an element. This is because Elements can't be broken down chemically into other substances because there is nothing to break them down into.
A pure substance that cannot be chemically broken down into simpler substances.
The simplest pure substances that cannot be broken down into any other substances are elements. Elements are made up of only one type of atom and cannot be separated into simpler substances by ordinary chemical reactions. Examples include hydrogen, oxygen, and carbon.
There are some substances, such as noble gases like helium and neon, that are chemically inert and cannot be broken down into simpler elements by metabolic processes in the body. These substances do not participate in chemical reactions due to their stable atomic structures.
Two substances that cannot be broken down by chemical change are elements and compounds. Elements are fundamental building blocks of matter that cannot be broken down into simpler substances by chemical reactions. Compounds are made up of two or more different elements chemically bonded together in fixed ratios, and they also cannot be broken down into simpler substances by chemical reactions.
All substances can be broken into any other substances (or elements) by chemical or physical methods.