When chemical W is added to a liquid, the chemical breaks down into substances X, Y, and Z. It is not possible to break down substances X, Y, and Z into simpler substances. What conclusion is supported by this evidence? Chemical W is an element.
Chemical Wis a pure substance
Substances X, Y and Z are elements.
Substances XY and Z are compounds

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hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds

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