Atomic Structure Chapter 4 Mr. Hines

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1 Atomic Structure Chapter 4 Mr. Hines Part A Standard model of the atom Learning Targets and I can statements 1 List, label, and describe the parts of an atom. 2 Identify the atomic number and the atomic mass of all elements and explain what they mean. 3 Describe atoms using the classical model. 4 Describe atoms using the Marble in the football stadium model. I CAN Part B Electrons and the Periodic Table 5 Define energy levels and explain how electrons are organized into energy levels. 6 Determine how many electrons can be held in each energy level. 7 Explain how electrons fill energy levels (aufbau principle). 8 Draw atomic models with proper amounts of subatomic particles. 9 Define valence electrons and determine the amount for each element. 10 Identify groups on the periodic table and explain the relationship between valence electrons and groups. 11 Determine the amount of energy levels for each element. 12 Identify periods on the periodic table and explain the relationship between energy levels and periods. 13 Compare and contrast the various elements on the periodic table. Part C - Isotopes 14 Define isotopes and write proper isotope notation. 15 Determine the number of all subatomic particles of an element when given the atomic mass of an isotope. 16 Compare and contrast isotopes of the same element. 17 Convert a percent to a decimal. 18 Calculate the atomic mass of each element from known scientific data. 19 Explain why the atomic mass of most elements is written as a decimal. 20 Name and draw the isotopes of Hydrogen. 21 Evaluate the placement of hydrogen and helium on the periodic table. Vocabulary Matter Atoms Protons Neutrons Electrons Amu Exist Atomic Subatomic Negative Positive Atomic Atomic Periodic Table mass units particles charge charge number mass Neutral charge Electron cloud Energy Level Vertical column Horizontal row Lewis dot structure Natural percent abundance Nucleus Bike symbol Space Model Volume Valence Electron Mass Period Group Abundance Big Mac Percent Aufbau principle Isotope Average Hydrogen Decimal Deuterium Tritium

2 PART A STANDARD MODEL OF THE ATOM Target 1 List, label, and describe the parts of an atom. A. Remember from earlier that matter is anything made of. B. Atoms are the basic building blocks of all matter. C. Atoms are made of smaller. These are listed below. 1. Protons positive charge (+) and found in nucleus (center) of atom. 2. Neutrons neutral or zero charge (0) and found in nucleus of atom. Collectively, protons and neutrons are referred to as (amu) term meaning that they are found in the nucleus. 3. Electrons negative charge (-) and found moving around the nucleus of an atom. Electrons have such a small that we don t even consider them when measuring mass.. Questions 1. List the parts of an atom. (3 parts) a. b. c. 2. Describe where the parts of an atom are located. a. b. c. 3. Indicate the charge on each part of the atom. a. b. c. Target 2 - Identify the atomic number and the atomic mass of all elements and explain what they mean. A. All of the elements are listed on the of Elements. B. Elements are different kinds of atoms with a name, symbol, and unique properties. C. The Periodic Table lists the elements in the order based on the number of. D. The atomic number is written above the symbol and tells you the number of protons. E. The number of protons identifies each individual element. F. The will also tell you the number of electrons.* G. The atomic mass is written below the symbol and tells you the total number of protons and neutrons. H. If you want to know the number of neutrons, you can subtract the atomic number from the atomic mass. I. Protons, neutrons, and electrons are collectively referred to as. J. Subatomic particles found in the nucleus (protons and neutrons) are more specifically called atomic mass units. K. Atomic mass units are abbreviated as amu.

3 Notes 12 Mg Questions 1. What is listed on the periodic table? 2. What is the difference between an element and an atom? 3. What determines the order in which elements are listed on the periodic table? 4. Where is the atomic number listed on the periodic table? 5. Where is the atomic mass listed on the periodic table? 6. What does the atomic number tell you about an element? 7. What does the atomic mass tell you about an element? 8. How do you determine the amount of neutrons in an element? 9. How many protons does Potassium have? 10. How many neutrons does Potassium have? 11. How many electrons does Potassium have? 12 How many subatomic particles does Potassium have? 13. How many atomic mass units does Potassium have? Target 3 Describe atoms using the classical model - Pg 129 A. The classical model of the atom. 1. Protons and neutrons are particles located in the nucleus. 2. Electrons around the nucleus. 3. It is known that electrons occupy a very large amount of space around the nucleus. 4. Since the electrons occupy a large around the nucleus, we call that space the electron cloud. 5. The electron cloud simply refers to the space where the electrons exist. 6. Label the electron cloud on the next illustration.

4 Target 4 - Explain the Marble in the football stadium model of an atom A. The classical model of the electron is commonly used around the world, but is not. B. A more accurate model of the atom is known as the marble in the football stadium. 1. If an atom were the size of a football stadium, the nucleus would be about the size of a marble. 2. Therefore, the electrons pretty much occupy all of the in the stadium. 3. In other words, atoms are 99.99% empty space! 4. Draw a marble in the center this stadium. PART B ELECTRONS AND THE PERIODIC TABLE Target 5 Define energy levels and explain how electrons are organized into energy levels 1. Energy Level - Specific location around the nucleus where electrons exist 2. Electrons are well organized in the electron cloud into 3. Energy levels can be visualized similar to planets orbiting around the sun each planet is further away from the sun and do not leave their orbits Solar system with planets revolving around sun Atom with electrons revolving around the nucleus 4. Energy levels around the nucleus are sort of like layers of an onion. 5. Energy levels can also be compared to rungs on a ladder if you climb a ladder, your feet will be on the rungs of the ladder. Pg There are a total of 7 energy levels.

5 Target 6 - Determine how many electrons can be held in each energy level. A. Energy levels can only hold so many electrons Notes box (drawing) Energy Amount of level electrons held Questions 1. What particles are found in the nucleus of an atom? 2. Where are the electrons of an atom? 3. Explain the marble in the stadium model of the atom. 4. What is meant by the electron cloud? 5. What is an energy level of the electron cloud? 6. How many electrons can be held in the 1 st energy level? 7. How many electrons can be held in the 2 nd energy level? 8. How many electrons can be held in the 3 rd energy level? 9. How many electrons can be held in the 5 th energy level? Target 7 - Explain how electrons fill energy levels A. Electrons will fill the innermost energy levels first (aufbau principle). B. When the innermost energy levels are filled, electrons must fill energy levels. C. This is similar to people filling around a boxing match once the front rows are filled, outer seating will fill up. D. For example has 3 electrons. 1. The first 2 electrons will fill the first energy level 2. The third electron will therefore be forced to exist in the second energy level. E. This concept is best learned through drawings. Target 8 - Draw atomic models with proper amounts of subatomic particles. Table Z Hydrogen Helium Lithium

6 Beryllium Boron Carbon Nitrogen Oxygen Fluorine Neon Sodium Magnesium Aluminum

7 Silicon Phosphorus Sulfur Chlorine Argon Potassium Target 9 - Define valence electrons and determine the amount for each element. A. Valence electrons electrons that are located in the outermost energy level. B. From the drawings on Table Z, determine the amount of valence electrons for each element. 1. Hydrogen = 2. Helium = 3. Lithium = 4. Beryllium = 5. Boron = 6. Carbon = 7. Nitrogen = 8. Oxygen = 9. Fluorine = 10. Neon = 11. Sodium = 12. Magnesium = 13. Aluminum = 14. Silicon = 15. Phosphorus = 16. Sulfur = 17. Chlorine = 18. Argon = Einstein moment - can you explain the arrangement of the elements on the periodic table based on valence electrons?

8 Target 10 - Identify groups on the periodic table and explain the relationship between valence electrons and groups. (Pg 118) 1. Groups on the periodic table are columns - draw a vertical line over here 2. For example, Sodium, Lithium and Hydrogen are all in the same group (group 1) 3. Groups on the periodic table are divided into 2 catagories. a. Group A b. Group B 4. In this chemistry class, we will mostly speak of. (Group B for advanced studies) 5. Label the groups on your periodic table as demonstrated in class Target 11 Determine the amount of energy levels for each element. A. From the drawings on Table Z, determine the amount of energy levels for each element. 1. Hydrogen = 2. Helium = 3. Lithium = 4. Beryllium = 5. Boron = 6. Carbon = 7. Nitrogen = 8. Oxygen = 9. Fluorine = 10. Neon = 11. Sodium = 12. Magnesium = 13. Aluminum = 14. Silicon = 15. Phosphorus = 16. Sulfur = 17. Chlorine = 18. Argon = Einstein moment - can you explain the arrangement of the elements on the periodic table based on energy levels? Target 12 - Identify periods on the periodic table and explain the relationship between energy levels and periods. (Pg 118) 1. Periods on the periodic table are columns (draw a horizontal line here) 2. For example, sodium, magnesium, and aluminum are all in the same period (period 3). 3. This means that elements in period 3 will all have 3 4. Label the periods on your periodic table as demonstrated in class

9 Practice Indicate which GROUP each element is in. Element Group Element Group Element Group Element Group Mg B C O Ca Al Si S Sr Ga Ge Se Practice Indicate which PERIOD each element is in. Element Period Element Period Element Period Element Period Li B N Ne Na Al P Ar Ca Fe Cu As 1. What is a group on the periodic table? 2. What is a period on the periodic table? Target 13 - Compare and contrast the various elements on the periodic table. 1. What is the definition of an element? 2. What is the definition of the periodic table? 3. How are elements alike? (compare) 4. How are elements different? (contrast) PART C - ISOTOPES Target 14 - Define isotope and write proper isotope notation A. Even though atoms are considered to be the same based on the amount of, they can have different amounts of neutrons. B. In nature, will contain different amounts of neutrons. C. Isotope - elements that have different numbers of neutrons D. If most elements have a different number of neutrons, how can the atomic mass number be determined? E. Whenever an Isotope is written, it includes the of the isotope after the symbol separated by a dash.

10 Practice Write the proper isotope notation for each example Helium Carbon Helium Carbon Nitrogen Nitrogen Target 15 - Determine the number of all subatomic particles of an element when given the atomic mass of an isotope Oxygen 17 Phosphorus - 33 Fluorine - 21 Copper - 66 Calcium - 42 Potassium - 41 Target 16 Compare and contrast isotopes of the same element.

11 Target 17 - Convert a percent to a decimal. A. A percent can be written as a decimal by moving the decimal point to the left 2 places. notes Percent Decimal Percent Decimal Percent Decimal 27% 976% 4% 1.2% %.56% Target 18 - Calculate the atomic mass of each element from known scientific data. A. Why is the atomic mass for each element written as? B. Even though atoms are considered to be the same based on the amount of protons, they can have different amounts of neutrons. 1. For example, a neon atom will always have 10. However, neon atoms can have different amounts of neutrons. 2. Because of this, neon atoms will have different atomic masses. C. The atomic mass number is calculated by the of its abundance in nature. D. In order to do this, you must know 3 things 1. The number isotopes of the element 2. The mass of each isotope 3. The natural percent abundance of each isotope. Carbon 1. The number of stable isotopes of the element 2. The mass of each isotope 3. The natural percent abundance of each isotope. C-12 C-13 notes % 1.11% The average mass reflects both the mass and the relative abundance of the isotopes as they occur in nature Calculate the average atomic mass for each element Natural Percent Abundance of Stable Isotopes of Some Elements Name Notation Natural percent abundance Mass (amu) Average atomic mass Hydrogen H % H-2 H % %

12 Helium He % He % Nitrogen N-14 N % % Target 19 Explain why the atomic mass of most elements is written as a decimal. notes Target 20 - Name and draw the isotopes of Hydrogen notes Target 21 - Evaluate the placement of hydrogen and helium on the periodic table Notes

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