Question

select all that are compounds.
a. o₂
b. kf
c. fe
d. cl₂
e. ici

Explanation:

Step1: Recall compound definition

A compound is a substance made up of two or more different elements chemically combined.

Step2: Analyze option A

$O_2$ is an oxygen molecule composed of two oxygen atoms (same element), so it is not a compound.

Step3: Analyze option B

KF is potassium fluoride, made up of potassium (K) and fluorine (F) - two different elements, so it is a compound.

Step4: Analyze option C

Fe is the element iron, a single - element substance, not a compound.

Step5: Analyze option D

$Cl_2$ is a chlorine molecule composed of two chlorine atoms (same element), not a compound.

Step6: Analyze option E

ICl is iodine monochloride, made up of iodine (I) and chlorine (Cl) - two different elements, so it is a compound.

Answer:

B. KF, E. ICl