Observe this chemical reaction:
4 Fe + 302– 2Fe2O3
How many reactants are there ?

The mass of a neutron is equal to the mass of a proton plus the mass of an electron. true or false false true

Which fact represents evidence for the big bang theory?

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.