Elaborate on whether this structural diagram represents an element or a compound. a) the compound is made up of multiple atoms. b) this element is made up of two different atoms. c) it is an allotrope representing a hydrobromide ion. d) this structural geometry shows elemental bromide. which of these is common to all chemical changes? a) a change of state occurs. b) a change of color occurs. c) a new substance is produced. d) heat is released into the air. molecules are different from atoms because they a) have less energy. b) are much smaller. c) have unique properties. d) contain chemical bonds. consider these four line graphs representing speed in meters/second, where each x-axis is labelled in seconds and each y-axis is labelled in meters. what do the four graphs have in common? a) they all indicate a constant speed. b) they all indicate an increase in speed. c) all four graphs have nothing in common. d) they all represent the same speed in m/s.