1. Review for Chapter 4 TEST Development of Atomic Theory. Group competition: The group with the most correct answers wins 5 e.c. points to add to their test grade. 1 st runner up will receive 2 e.c. points.

2. List the postulates of Dalton’s Atomic Theory.  Elements are made of tiny particles called atoms.  All atoms of a given element are identical.  All atoms of a given element are different from the atoms of other elements.  Atoms can combine with each other(in small whole number ratios) to form different compounds. (ex: NO, NO 2, N 2 O)  Atoms are indivisible.

3. Which of Dalton’s postulates had to be changed?  All atoms of a given element are identical.  Atoms are indivisible.

4. Whose experiment first proved that atoms were divisible?  JJ Thomson

5. What discovery led to the change from all atoms of the same element are identical, to all atoms of the same element are chemically identical?  The discovery of isotopes.

6. What are isotopes?  Atoms of the same element with different numbers of neutrons.  They have different masses, but the same chemical properties.

7. If an element has an atomic number of 29, which element is it?  Cu

8. If an element has 13 protons, list its atomic number and symbol  Atomic number 13, Al

9. If an element has 6 protons and 7 neutrons, what isotope is it?  C-13

10. Which law does this illustrate? Who discovered it? The Law of Conservation of Matter, discovered by Lavoisier.

11. Which law does this illustrate? The Law of Multiple proportions.

12. Which law does this illustrate? The Law of Definite proportions, discovered by Proust. These are six water molecules: Each has one oxygen and two hydrogen atoms. Each has a mass ratio of 8:1 oxygen to hydrogen

13. Which of the above = number of protons? Atomic number: 8

14. What does this picture illustrate? The three isotopes of hydrogen have the same number of protons and electrons, but varying numbers of neutrons. The electrons are located outside of the nucleus, protons and neutrons are located inside the nucleus.

15. What are the nuclear particles?  Protons (p + )  Neutrons (n o )

16. What is the mass of hafnium if, out of every 100 atoms 5 have mass of 176 amu, 19 have mass of 177 amu, 27 have mass of 178 amu, 14 have mass of 179 amu, and 35 have mass of 180.0 amu?  5/100 (176 amu) = 8.80 amu  19/100(177 amu)= 33.6 amu  27/100(178 amu)= 48.1 amu  14/100(179 amu)=25.1 amu  35/100(180 amu)=63.0 amu  The sum = average atomic mass  Average atomic mass = 178.6 atomic mass units

17. IsotopeAtomic number Number of protons Number of electrons Mass number H-1 H-2 C-13 P-32 Fill in the chart.

18. Isotopes IsotopeAtomic number Number of protons Number of electrons Mass number H-11111 H-21112 C-136113 P-3215 32

19. Fill in the Chart IsotopeAtomic # # protons # neutron Mass number gallium-61 Germanium -62 Germanium -63 Bromine-69

20. Fill in the Chart. Isotope Atomic number Number of protons Number of neutrons Mass number gallium-61 31 3061 Germanium -62 32 3032 Germanium -63 32 3163 Bromine-69 35 3469

21. If this is carbon, which color represents the protons? (black, blue, yellow, orange,or transparent green.)

22. If this is carbon, which color represents the nucleus? (black, blue, yellow, orange,or transparent green.)

23. If this is carbon, which color represents the electrons? (black, blue, yellow, orange,or transparent green.)

24. The End  Add up your points.  The two teams with the most points turn in their cards for the extra credit on the test.