. A student observes what happens when two different aqueous solutions are mixed in a test tube. Which of the following observations would be most indicative of a precipitation reaction?
Gas bubbles are produced.
There is a color change.
The test tube warms.
A solid settles out.

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

Great amounts of electromagnetic energy from our sun and other bodies in space travel through space. which is a logical conclusion about these electromagnetic waves? their energy must be very their frequency must be very low these waves can travel without a medium they only travel through a vacuum of space

What occurs when a cell engulfs large food particals