Combining and Separating

Why does sand settle to the bottom of the ocean, but salt mixes in? How do people get sea salt out of the sea?


Could you tell the difference between sugar and salt without tasting them? Have you ever seen a crystal up close? How are crystals made?


How does panning for gold work? Why is it hot at the top of a pool, and colder at the bottom?

Air Pressure

How do suction cups work? Is there anything they can’t stick to?