Name ______Date ______P___R___S____

Honors Chemistry

Unit 2: How did the Atomic Model Evolve

Test Study Guide

2.1 Recognize discoveries from Dalton (atomic theory), Thomson (the electron), Rutherford (the nucleus), and Bohr (planetary model of atom) and understand how these discoveries lead to the modern theory.

i) History of Atomic Model (PPT) – Cathode Ray Experiment and Gold Foil Experiment Pictures

ii) Atomic Model Worksheet (1)(2)(3) iii) Atomic Model Study Guide

iv) Atomic Model 5 Pictures (on Weebly)

A) Who came up with the first idea about atoms? ______

B) Who created Atomic Theory? ______C) Who discovered the electrons? ______

D) Who discovered positive nucleus & atomic empty space? ______

E) Who discovered energy levels? ______F) Who developed orbitals? ______

G) Cathode Ray Experiment - Atomic Model Worksheet (2) – You need to know:

a) Describe the experiment with the pictures and how the experiment was run. Include a picture.

b) What was the prediction? Include a picture.

c) What was the actual experimental result? Include a picture.

d) What were the conclusions?

F) In the order of Atomic model History (From Dalton to Modern Scientists):

i) Scientists’ Namesii) Atomic Model Namesiii) Atomic Model Pictures (w/ LABELS)

(Rutherford’s Model has two names!)

2.2 Describe Rutherford's "gold foil" experiment that led to the discovery of the nuclear atom. Identify the major components (protons, neutrons, and electrons) of the nuclear atom and explain how they interact.

A) Gold Foil Experiment – Atomic Model Worksheet (1) – You need to know:

a) Describe the experiment with the pictures and how the experiment was run. Include a picture

b) What was the prediction? Include a picture

c) What was the actual experimental result? Include a picture

d) What were the conclusions?

B) Atomic Structure:

Draw the Bohr Diagram for the following elements. Fill in the table.

Atomic Name: Nitrogen Atom / Atomic Name:
Atomic number: 7 / Atomic number:
Mass number: / Mass number: 16
Protons: / Protons: 7
Neutrons: / Neutrons:
Electrons: / Electrons:
Charge: 0 / Charge:
Atomic Symbol: / Atomic Symbol:
Atom / isotope? / Atom / isotope?

What is valence electron? ______

What is the pattern of the valence electron on the same vertical column in the periodic table?

______

C) Average Atomic Mass (Show all your work with units and element symbols!)

  1. Naturally occurring chlorine that is put in pools is 75.53 percent Cl-35 (mass = 34.969 amu) and 24.47 percent Cl-37 (mass = 36.966 amu). Calculate the average atomic mass. (The answer would be 1 digit off)
  1. Lithium-6 is 4% abundant and lithium-7 is 96% abundant. What is the average mass of lithium? (The answer would be 1 digit off)

D) % Abundance (Show all your work with units and element symbols!)

1. Boron has only two naturally occurring isotopes. The mass of boron-10 is 10.01294 amu and the mass of boron-11 is 11.00931 amu. Calculate the percentage abundance of boron-10 and boron-11.

(~ 20%, ~ 80% - but not exactly like this – Need to be 2 decimal places!)

2. Determine the % Abundance of the two isotopes of Chlorine (Cl-35 and Cl-37). (~78%, ~23%)

2.4 Write the electron configurations for the first twenty elements of the periodic table.

What are the four shapes of orbitals? _____,______,_____,_____

How many electrons for each orbital can hold respectively? s ( ), p ( ), d ( ), f ( )

A) Write the full electron configurations of the following elements. Show valence e- (underline the highest energy level, circle the electrons, show the addition if there are, and add units).

1. Calcium ( ) ______

2. Fluorine ( ) ______

3. Neon ( ) ______

4. Iron ( ) ______

B) Write the shorthand electron configurations of the following elements. Show valence e- (underline the highest energy level, circle the electrons, show the addition if there are, and add units).

5. Potassium ( ) ______

6. Chlorine ( ) ______

7. Argon ( ) ______

8. Zinc ( ) ______

C) Determine what elements are denoted by the following electron configurations (Just the element symbol):

7. 1s22s22p63s23p5 ______

8. 1s22s22p63s23p64s23d104p65s2 ______

9. [Kr] 5s24d105p4 ______

10. [Ar] 4s23d9 ______

D) i) If the following electron configuration are valid, write the word “valid” And identify the element.

ii) If the following electron configurations are not valid, write the word “invalid” And tell the reason why they are not valid. Correct the whole electron configuration

11. 1s22s22p63s23p64s23d84p5 ______

12. 1s22s22p63s43d5 ______

13. [Ra] 7s25f8 ______

14. [Kr] 5s24d105p5 ______

15. [Xe] ______

2.5 Identify the three main types of radioactive decay (alpha, beta, and gamma) and compare their properties (composition, mass, charge, and penetrating power).

Name / Alpha
Greek letter / - / + / 
Atomic Symbol /
Composition
Mass
Charge / 0
Stopped by
Penetrating Power

2.6 Describe the process of radioactive decay by using nuclear equations and explain the concept of half-life for an isotope, for example, C-14 is a powerful tool in determining the age of objects.

A) Nuclear Equations

B) Half Life

2.7 Compare and Contrast Nuclear Fission and Fusion

Complete the following fission and fusion nuclear equations. Circle either fission or fusion.

What are the differences of nuclear fission and nuclear fusion?

______

______

______

______

Give as many examples as you can.

______

______

Directions: Identify each as a fusion, fission.

1. Used in nuclear power plants:

2. Occurs on the sun:

3. A larger nucleus divides to make a smaller nucleus:

4. Two hydrogen atoms fuse to make a helium atom: ______

5. A critical mass is necessary to explode: ______

6. :

7. An atomic bomb: ______

8. is the minimum amount of material needed to sustain a nuclear reaction.

9. are used in nuclear power plants to keep the reaction under control.

10. would cause air pollutions.

11. ______would not cause air pollutions.