Question

Your teacher gives you a black powder. When you dissolve the powder in water, you see red particles that float to the top, black particles that sink to the bottom, and a green liquid.

What was the black powder?

Responses

pure substance

pure substance

compound

compound

element

element

mixture

mixture

Answer 1

mixture

Reason: dissolving produced multiple distinct components (red solids, black solids, green liquid) that physically separate (float/sink), so it’s a heterogeneous mixture rather than a single pure substance, compound, or element.