Across
- 1. the area of an enzyme where the substrate attached
- 3. the amount of energy required to begin a reaction
- 4. valence electrons are shared
- 9. tells how much radiation an isotope is giving off
- 12. a reaction that retains heat
- 15. the starting elements left of the arrow
- 16. neutral, used to calculate atomic mass
- 17. vertical rows of the periodic table
- 18. pure substance that cannot be broken down
- 21. atoms with full valence electrons
- 24. a certain type of atom
- 25. when the nucleus breaks apart and radiation is emitted
- 26. two or more elements combine to form something new
- 27. The study of atoms
- 28. building blocks of matter
- 29. a biological catalyst
Down
- 2. polar molecules combine to form hydrogen bonds
- 5. a reaction that gives off heat
- 6. the reactants that bind to the enzyme
- 7. negatively charged, orbit the nucleus
- 8. horizontal rows of the periodic table
- 10. a substance that lowers the activation energy required to start a reaction
- 11. the sum of protons and neutrons in an atom
- 13. atoms with a different number of neutrons
- 14. a charged particle
- 19. the giving and taking of electrons to form a bond
- 20. the result of a chemical reaction, right side of the arrow
- 22. positively charged, equal the atomic number
- 23. compound held together with a covalent bond