Explain the expression “light travels at a speed”.

Explain using examples, what is simple harmonic motion and why it is an important area of study in physics.

When fat comes in contact with sodium hydroxide, it produces soap and glycerin. determine whether this is a physical change or a chemical change. explain your answer

These models show the electron structures of two different nonmetal elements. which element is likely more reactive, and why? element 1 is more reactive because it has fewer electron shells and is toward the top of its group on the periodic table. element 1 is more reactive because it has more electrons in its valence shell and is farther to the right on the periodic table. element 2 is more reactive because it does not have a valence shell close to the nucleus, so it will attract electrons. element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.