1. Board Review 1) (-) charged 2) located in nucleus 3) equal to atomic # 4) no charge 5) (+) charged 6) lightest particle 7) determines chemical properties 8) transferred or shared in chemical bonds proton, neutron, electron Chapter 4: Atomic Structure

2. Atomic mass # Atomic Structure (Board Review) atomic # 12.011 11 10 9 12 13 14

3. 15. Longhand =16. Shorthand = Atomic Structure (Board Review)

4. Potassium-39Potassium-40 Atomic Structure (Board Review)

5. 20n o Mass # 39 stable 21 n o Mass # 40 unstable/radioactive 19p+ 19e - Atomic # Reactivity Potassium-39Potassium-40 Atomic Structure (Board Review)

6. Atomic Structure Notes

7. Protons 1) (+) charged 2) located in nucleus 3) = to atomic #

8. Protons 5) actual mass = 1.67 x 10 -24 g 6) Relative mass = 1 amu (atomic mass unit)

9. Neutrons 1) located in the nucleus 2) no charge

10. Neutrons 3) how calculated: ◦ Mass number ◦ - Atomic number ◦ # neutrons *Example – fluorine  19 = mass number  -9 = atomic number  10 = number of neutrons

11. Neutrons 5) actual mass = 1.67 x 10 -24 g 6) Relative mass = 1 amu *approximately same as mass of proton*

12. Electrons 1) (-) charged 2) located in space surrounding nucleus (= electron cloud)

13. Electrons 3) equal to # of p + (atomic #) if neutral

14. Electrons 4) may be transferred or shared to form chemical bonds

15. Electrons 6) actual mass = 9.11 x 10 -28 g 7) relative mass = 1/1840 amu ◦ *it takes 1840 electrons to equal mass of 1 proton*

16. REVIEW 1) How many protons in an atom of barium? 2) Describe the composition of a helium nucleus. 3) How many electrons in an atom of fluorine? 56 2 p+ & 2 n o 9

17. REVIEW 4) Where are the electrons in an atom? 5) How many neutrons are in an atom of germanium? In the electron cloud orbiting the atom. 41

18. Review 11) How are protons and neutrons similar? 12) How are protons and electrons similar? Mass Location in nucleus Equal # if neutral Discovered Both have a charge

19. Review Which particle(s)…. 13) determine chemical reactivity? 14) are located in the nucleus? 15) may be transferred between atoms? 16) have a positive charge? 17) are always equal to the atomic #? 18) have a mass of 1 amu? 19) vary with isotopes? 20) are negatively charged? e-e- e-e- e-e- p+ & n o p+ p+ & n o no no

20. E. Comparing Subatomic Particles Sub atomic particle SymbolCharge How calculated? Location Relative mass other protonp++Atomic #Nucleus1 amuAtom ID electrone--Equal to #pElectron cloud (empty space) 1/1840 amu bonding neutronn˚0 Mass # - atomic# Nucleus 1 amuVary in isotopes

21. A. Atomic Number 1) equal to # protons 2) if neutral, also equal to number of electrons 3) identifies the type of atom (element) 108 Ag 47 Atomic Number Mass Number

22. B. Mass Number 1) equal to the number of protons + neutrons combined What is the mass number for pictured atom? 12

23. B. Mass number 2) Atoms of the same element may differ in the number of neutrons, resulting in different mass numbers

24. B. Mass Number 3) mass number on the periodic table is weighted average for all atoms of that element *How many neutrons do the majority of lithium atoms have? 4

25. Review 1) What is the atomic number of iron? 2) What is the mass number of bromine? 3) How many protons do calcium atoms have? 4) How many neutrons do neon atoms have? 26 80 20 10

26. C. Isotopes 1) isotopes =different atoms of the same element with different numbers of neutrons

27. C. Isotopes 2) all isotopes of the same element have the same CHEMICAL reactivity 3) isotopes differ in nuclear stability

28. D. Symbols 1) Shorthand method ex. =

29. D. Symbols 2) long method ex. = Potassium-39 *39 = mass number

30. Review 1) Write the shorthand for aluminum-27. 2) How many neutrons in an atom of uranium-235? 3) Is lithium-7 more or less chemically reactive than lithium-6? 27 Al 13 143 Neither, they are isotopes so their chemical reactivity is the same.

31. Review 4) 40 K has how many neutrons? 5) Write the shorthand for an element containing 53 protons and 78 neutrons. 6) Write the longhand for an element containing 1 proton and 0 neutrons. 21 131 I 53 Hydrogen-1