Unit 4 Vocab Test

4. a chemical reaction in which energy is released to the surroundings
6. atoms with the same number of protons but different numbers of neutrons
12. process in which atoms are rearranged to produce new substances
14. an expression that uses symbols to show the relationship between the starting substances and the substances that are produced by a chemical reaction
17. substances that participate in a chemical reaction
18. a process by which nuclei of small atoms combine to form a new, more massive nucleus
19. substances formed in a reaction

1. nuclear reaction in which a large unstable nucleus breaks into two smaller nuclei
2. nuclear reaction in which an unstable nucleus can give off energy and, sometimes, particles
3. a chemical compound that is composed of carbon, hydrogen, and possibly other elements
5. neutral organic compound containing carbon, hydrogen, and oxygen
7. law that states that matter is neither created nor destroyed
8. organic compound that contains only carbon atoms and hydrogen atoms
9. a chemical reaction that requires an input of energy
10. law that states energy cannot be created or destroyed
11. a way to represent a given substance using chemical symbols and numbers
13. molecules composed of the same repeating small groups of atoms joking in long chains
15. a change that affects the nucleus of an atom
16. organic compound that has acidic properties