Atomic Theory and the Periodic Table Review What are the

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Atomic Theory and the Periodic Table Review

What are the contributions of the following people to the atomic model? For those that resulted in a revision to the model. Draw the model they proposed.

Democritus- originally named atom; atom model is solid homogenous sphere

Dalton- proposed the atomic theory, atom model is solid homogeneous sphere

Thomson- proved the existence of negative particles through work with cathode ray tubes; atom model had negative particles embedded in positive matrix (also called plum pudding model)

Rutherford- proved the existence of the nucleus with gold foil experiment; atom model had positive particles in a nucleus surrounded by electron

Chadwick- discovered the neutron

Bohr- atom model had a nucleus of protons and neutrons surrounded by electron in fixed orbits like planets orbiting the sun

Give the charge and location of each of the subatomic particles.

Particle Charge Location

Proton

Neutron

__+_____

__0_____

__nucleus__________

__nucleus__________

_orbiting nucleus______ Electron

Define the following:

__-_____

Atomic Number- number of protons in an atom

Mass Number- number of particles in the nucleus (protons + neutrons) in a particular atom

Atomic Mass- average mass of all the naturally occurring isotopes of an element according to their abundance

Isotope- atoms of the same element that differ in their number of protons

(and so also differ in their mass number)

Ion- atom with a charge because of the number of protons and electrons are unequal

Cation- a positively charged ion; occurs when a neutral atom loses electrons

Anion- a negatively charged ion; occurs when a neutral atom gains electrons

Calculate the number of protons, neutrons, and electrons of the following isotopes.

Isotope # of Protons # of Neutrons # of Electrons

Hydrogen-3

Hydrogen-2

1

1

2

1

1

1

Calcium-40

Copper-63

Iodine-127

Barium-137

20

29

53

56

20

34

74

81

20

29

53

56

Write the nuclear symbol for each of the isotopes in the previous problem

_ 3 H__ __ 2 H __ ___ 40 Ca __ ___ 63 Cu __ ___ 127 I __ ___ 137 Ba ___

Calculate the number of protons, neutrons, and electrons of the following ions.

Ion

37 Cl

-

# of Protons

17

# of Neutrons

20

# of Electrons

18

22 Na

+

28 Mg

+2

14 N

-3

11

12

7

11

16

7

10

10

10

Name each of the following ions. Multivalent ion are in bold.

Fe +3 __iron (III) ion_________

S -2 __sulfide ion___________

Li + __lithium ion___________

I __iodide ion____________

Calculate the average atomic mass of the following problems.

Silver (Ag) is found as two isotopes (silver-107 and silver-109). What is the average atomic mass if the abundance of silver 107 is 51.86%?

107 x 0.5186 = 55.4902

109 x 0.4814 = 52.4726

55.4902 + 52.4726 = 107.96 amu

Iron has four isotopes (listed with their abundances below). Calculate the average atomic mass.

Iron-54

Iron-56

5.90%

91.72%

Iron-57

Iron-58

2.10%

0.280%

54 x 0.0590 = 3.186

56 x 0.9172 = 51.3632

57 x 0.0210 = 1.197

58 x 0.00280 = 0.1624

3.68 + 3.666 + 35.232 + 2.695 = 55.91 amu

Who is the “father” of the period table? Mendeleev

The modern periodic table has the elements arranged by their _atomic number___ forming columns called _groups or families___ and rows called _periods_______.

What group numbers are each of the following?

Alkali metals- 1

Alkaline earth metals- 2

Halogens- 17 (7A)

Nobel gases- 18 (8A)

Transition elements- 3-12

Name at least three characteristics of metals and nonmetals.

Various (see notes)

For each of the following elements, determine if it is a metal, metalloid, or nonmetal.

Na __metal__________________

Si __metalloid________________

N __non-metal________________

Ar __non-metal________________

U __metal___________________

Pb __metal__________________

List the seven diatomic elements. N, O, F, Cl, Br, I

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