If you move a substance from one container to another and its volume changes substances is gas.
Answer:
The gravitational pull of a black hole is so strong that nothing, not even light, can escape once it gets too close. ... Moving at close to the speed of light, these particles ricochet off the event horizon and get hurled outward along the black hole's axis of rotation
(True)
Safety glasses should be worn any time you are doing an experiment, especially one that involves chemicals or chemical reactions. They prevent chemicals or other materials from getting on or in your eye, and can prevent anything from mild discomfort to permanent blindness.
Some pairs of safety glasses have magnifying glasses on them, similar to bifocals. They can be used to more carefully examine something in an experiment.
Relatively few hydrogen atoms
