Classify each of the following pure substances as an element or a compound: helium gas (He), mercury (Hg) in a thermometer, vinegar (C, H402), sulfur (S), lye (KOH).

Drag the appropriate items to their respective bins.

Element: helium gas (He), sulfur (S)

Compound: vinegar (C,H402), lye (KOH)
Unknown: mercury (Hg) in a thermometer

Element: helium gas (He), sulfur (S)

Compound: vinegar (C, H402), lye (KOH)
Not enough information: mercury (Hg) in a thermometer