Why are all of the substances on the periodic table classified as elements? substances on the periodic table cannot be broken down into other substances and are therefore elements. substances on the periodic table can be combined to form compounds and are therefore elements. substances on the periodic table cannot be dissolved in water or other liquids. all elements are pure substances. - which subatomic particle has a negative charge? electron proton neutron all particles

If we compare and contrast electromagnetic waves with sound waves, all but one statement is true. that is a) sound waves require a medium to travel while electromagnetic waves do not. b) electromagnetic waves can travel through the vacuum of space while sound waves cannot. c) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere. eliminate d) sound waves must bounce off of matter in order to travel while electromagnetic waves do not require matter to be present.