Which type of matter consists of two or more substances that are not chemically combined? A)Elements
B)Mixtures
C)Compounds
D)Pure Substances

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.

Suppose a pair of chemical compounds a and b can react in two different ways: a + b -> c reaction 1 gives product c. a + b -> d reaction 2 gives product d. the following facts are known about the two reactions: . reaction 1 is endothermic and reaction 2 is exothermic. if a reaction vessel is charged (filled) with a and b , then at first d is produced faster than c. use these facts to sketch a qualitative reaction energy diagram for both reactions. note: because these sketches are only qualitative, the energies don? t have to be exact. they only have to have the right relationship to each other. for example, if one energy is less than another, that fact should be clear in your sketch.

Compare and contrast an assemblage and a pollen fingerprint by defying both and giving examples of each from the chapter.