Question

A mixture of very finely ground iron particles and sand particles could best be separated in lab by:

a magnet

adding water and filtering the metals

comparing their boiling points

comparing their melting points

Answer 1

Answer is: a magnet.

1) A magnet is attracted to magnets (ferromagnetic), sand is not.

2) Iron and sand do not dissolve in water, so if they are filtered, both substances will stay on filter paper.

3) Iron (Fe) and sand (SiO₂) boiling points are very close, around 1900°C.

4) Iron and sand melting points are very close, around 1550°C.