Question

ellie was comparing samples of substances to determine if they were a pure substance or a mixture. ellie classified samples a and b as mixtures and sample c as a pure substance.
is ellies classification correct? why or why not?
a she is correct because samples a and b both contain sample c and therefore are considered mixtures.
b she is incorrect because sample b contains different types of substances and should be classified as a pure substance.
c she is incorrect because sample a contains only one type of substance and should be classified as a pure substance.
d she is correct because samples a and b both contain different substances to make mixtures and sample c is made up of one substance to be a pure substance.

Explanation:

Step1: Analyze Sample A

Sample A has only one type of particle (molecules). A pure substance has a uniform composition. So, if it were a pure - substance sample, it should be classified as a pure substance. But Ellie classified it as a mixture.

Step2: Analyze Sample B

Sample B has two types of particles (molecules and single atoms). A mixture has a non - uniform composition (more than one type of particle). So, it should be classified as a mixture. But Ellie's classification for A and B as mixtures is wrong in the case of A.

Step3: Analyze Sample C

Sample C has only one type of particle (atoms). A pure substance (like an element, if it's made of single atoms) has a uniform composition. So, it should be classified as a pure substance.

Answer:

B. She is incorrect because Sample B contains different types of substances and should be classified as a pure substance.