When Phillip analyzed an unknown substance X, he found that it contained only one kind of atom. Phillip was unable to convert the substance to a simpler one. What is substance X?

A.

a compound

B.

an element

C.

a heterogeneous mixture

D.

a homogeneous mixture

Answer: -

Substance X is a (B) Element.

Explanation: -

A compound consists of either many identical atoms or more than 1 type of atom. They can be broken down or converted into a simpler one.

An element is a substance which contains only one kind of atom. It cannot be broken down further or converted into simpler substance by any chemical means.

Heterogeneous mixture is a non uniform mixture of different atoms without any chemical bonding in between them.

Homogeneous mixture is a uniform mixture of different atoms without any chemical bonding in between them.

From the definitions it is clear that substance X is (B) Element.