The element sodium reacts explosively with water and the element chlorine is a yellowish-green poisonous gas. When chemically combined, sodium and chlorine form
nonexplosive, nonpoisonous table salt. Explain how this can be.
Identify each of the following as an element, a mixture, or a compound.

Which statement is a reason to support population regulation? a) it is unethical for us to control birth control rates b) humans have the freedom to produce as many children as desired c) the gap between the rich and poor has been narrowing since 1960 d) billions more people on the earth will intensify many environmental and social problems

Frictional forces acting on an object are often converted into energy, which causes the temperature of the object to rise slightly.

In a water molecule, hydrogen and oxygen are held together by a(an) bond. a) double covalent b) ionic c) nonpolar covalent d) hydrogen e) polar covalent