1. Review

2. What was wrong with Dalton’s atomic theory?

3. His atom had no subatomic particles, and he thought the atom was solid. He also thought all atoms of the same element were identical. This is wrong. Now we know about isotopes.

4. Which of the scientists discovered the nucleus and discovered the fact that most of the atom is empty space?

5. Rutherford

6. Which scientist placed the electrons in energy levels orbiting the nucleus?

7. Bohr

8. Who came up with the “plum pudding” model of the atom?

9. Thomson

10. State the law of definite proportions.

11. A chemical compound contains the same elements in exactly the same proportions by mass regardless of the size of the sample. For example, NaCl always contains 39% sodium(Na) by mass and 61% chlorine(Cl) by mass.

12. What is the atomic number of an element?

13. The number of protons.

14. Which of the subatomic particles has no charge?

15. neutron

16. What does the number 4 mean in the hyphen notation hydrogen-4?

17. 4 is the mass number, the number of protons plus neutrons.

18. How many protons, neutrons, and electrons are in 13 C ? 6

19. 6 protons 7 neutrons 6 electrons

20. What is the mass in grams of 3.50 moles of copper, Cu?

21. 3.50 moles Cu x 63.55 g Cu = 222 g Cu 1 mole Cu

22. How many moles of Mg are in 12.15 g of Mg?

23. 12.15 g Mg x 1 mole Mg = 0.5000 mole Mg 24.31 g Mg

24. How many moles of Pb are there in 1.50 x 10 12 atoms of Pb?

25. 1.50 x 10 12 atoms of Pb X 1 mole of Pb = 6.02 x 10 23 atoms of Pb 2.49 x 10 -12 mole Pb