Answer:
b It was a compound.
Explanation:
<em>A chemical reaction was used to separate a sample into its components. What conclusion about the sample can be formed based on the technique used? </em>
<em>a It was a pure substance.</em> NO. If the pure substance is a compound, this option could be. However, if the pure substance is a simple substance, it could not be separated into its components.
<em>b It was a compound.
</em> YES. Compounds can be separated into pure substances using chemical reactions. For instance, H₂O → H₂ + 1/2 O₂
<em>c It was a heterogeneous mixture.</em> NO. Heterogeneous mixtures can be separated into homogeneous mixtures using physical processes such as sieving, filtration, etc.
<em>d It was a homogeneous mixture.</em> NO. Homogeneous mixtures can be separated into pure substances using physical processes such as distillation, chromatography, etc.