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Home , Isotopes of argon, Isotopes of silicon

Chemistry Unit 3: Atoms and Nuclear Chemistry Name ______Chapter 3: Pages 74-91* Block ______Chapter 21: Pages 649-671* 100% Complete Yes No

Learning Targets Learning Test #1 Test #2 Target Assessment I can compare and contrast subatomic particles.

I can explain and determine the atomic number and of elements, and molar mass of compounds. I can understand the concept of and how the and relative atomic mass are calculated. I can calculate molar conversion problems.

I can identify, describe and write the nuclear equations for alpha, beta, gamma and neutron decay; I can compare fission and fusion reactions and applications of each.

Please note – Learning Target Checks (LTCs) cannot be retaken. Test #1 is worth 25 points and Test #2 is worth 15 points. Test #3 (taken on the day of the term test) will be worth 10 points and with completion of this learning packet the opportunity to replace Test #1 score with the sum of Test #2 and Test #3 is available. You are strongly encouraged to monitor your level of understanding for the learning targets using the table above.

*Modern Chemistry – Sarquis.Sarquis; Houghton, Mifflin, Harcourt (2017) Questions adapted from: Sarquis, M, Sarquis, J.L. (2017). Modern Chemistry Orlando, Florida: Houghton, Mifflin, Harcourt

LT 1: I can compare and contrast subatomic particles.

Practice Problems:

1. What is an atom? What does the term “atom” literally mean? (Look up if not sure)

2. Describe the 2 regions that make up an atom.

3. Subatomic Particle Location Size Charge (symbol) Proton (p+)

Electron (e-)

Neutron (no)

1 4. Draw and label the parts of an atom.

5. Where is most of the mass of an atom located and why? Where is most of the volume of an atom?

6. Write whether the following characteristics pertain to protons (P), neutrons (N) or electrons (E). You may use more than one letter on each line! a) ______Determines an element’s identity. b) ______Has a mass of 1 AMU c) ______An atom’s average atomic mass includes this type of subatomic particle. d) ______Is found in the nucleus of an atom e) ______Has a positive charge f) ______Has a neutral charge g) ______These subatomic particles can vary and ions form when they are gained/lost h) ______Is found outside the nucleus of an atom i) ______Has a negative charge j) ______Has a mass of that is estimated to be 0 AMU k) ______Subatomic particle used to determine the atomic number. l) ______Makes up most of the mass of an atom m) ______Are the smallest of all 3 subatomic particles n) ______These subatomic particles can vary and form different isotopes. o) ______These subatomic particles are found in orbitals/energy levels. p) ______Subatomic particle used to determine an element’s chemical properties. q) ______The number of these subatomic particles present determines the charge.

LT 2: I can explain and determine the atomic number and atomic mass of elements, and molar mass of compounds.

Practice Problems:

1. What is the atomic number? Identify, if possible, in the image to the right.

2. What is mass number? Identify, if possible, in the image to the right.

3. What is the relative atomic mass? Identify, if possible, in the image to the right.

2 4. Answer the following questions about different formats for writing elements:

Ca-40 Element ______Atomic # ______What does the 40 represent? ______

Carbon – 14 Atomic # ______What does the 14 represent? ______

ퟑퟔ 퐂퐥 Element ______Atomic # ______What does the 36 represent? ______ퟏퟕ

5. In a neutral atom, the atomic number tells you the number of ______and ______

in one atom of an element.

6. In order to calculate the number of neutrons you must subtract the ______from the

______.

7. Give the symbol and number of protons and electrons in a neutral atom of: ______Protons______Electrons______Boron ______Protons______Electrons______8. Name the element that has the following numbers of subatomic particles: a. 26 electrons, 29 neutrons, 26 protons ______c. 53 protons, 74 neutrons ______b. 2 electrons (neutral atom) ______d. 20 protons ______e. 15 protons ______

9. If you know only the following information can you always determine what the element is? If the answer is 'No' explain why not.

a. number of protons

b. number of electrons in a neutral atom

c. number of neutrons

d. number of electrons

10. What are isotopes? Describe an example.

11. Identify the following pairs of elements as isotopes or different elements. a. Element A has 42 protons and 50 neutrons Element B has 42 protons and 51 neutrons ______b. Element X has 54 protons and a mass number of 124 Element Z has 54 protons and a mass number of 130 ______c. Element C has 38 neutrons and an atomic number of 22 Element D has 38 neutrons and an atomic number of 23 ______12. There are three stable isotopes of : Argon-36, Argon-38, and Argon-40. What would the atoms of these isotopes have in common? What would be different about their atoms?

3 13. Can two atoms with the same mass number ever be isotopes of each other? Explain.

14. Fill in the following missing parts in the charts below:

Symbol Protons Electrons Mass Number Atomic Number Neutrons

28 42

Cl-36

-87 37 37

14 6

59 65

U- 234

7 9

33 42

15. Fill in the following missing parts in the charts below (note: charges are included this time!)

Symbol Atomic Number Mass Number Protons Neutrons Electrons

52 Cr 3+

25 30 25

19 21 18

133 55 54

80 Br 1-

16. What is molar mass?

17. Describe how molar mass is calculated.

4 18. Determine the molar mass of the following:

KClO4 g/mol Pb(SO4)2 g/mol

SnI4 g/mol (NH4)3PO4 g/mol

Ca(NO3)2 g/mol C6H12O6 g/mol

LT 3: I understand the concept of isotopes and how the mass number and relative atomic mass are calculated. **POGIL – Average Atomic Mass (first 3 questions below taken from: POGIL Activities for High School Chemistry. 2012. The POGIL Project and Flinn Scientific, Inc. Example Calculations:

Practice Problems:

1. The average atomic mass of is 14.0067amu. Predict which listed below is most abundant in nature? a. N-13 b. N-14 c. N-15

2. Explain why a weighted average is used to calculate the average atomic mass of an element. Why is it not sufficient to calculate a simple average of the isotope data?

5 3. A mystery element, called ‘muriacticum’ by its discoverer, exists on Earth as a mixture of two isotopes. The most abundant isotope (75.76%) has a mass of 34.9689amu; the other isotope (24.24%) has a mass of 36.9659 amu. Calculate the average atomic mass and identify the element by its modern name.

4. Calculate the average atomic mass of :

ퟏퟐ ퟏퟑ 퐂 퐂 ퟔ ퟔ Actual Mass Actual Mass Average Atomic Mass = ______12.000000 amu 13.003355 amu 98.90% abundant 1.10% abundant

5. Determine the average atomic mass of the following: There are 4 isotopes of an unknown element. If out of 100 atoms, 28 have a mass of 171 amu, 45 have a mass of 172 amu, 12 have a mass of 174 amu and 15 have a mass of 178 amu.

6. When a sample of natural is vaporized and injected into a mass spectrometer, the results show the sample is 69.09% copper-63 and 30.91% copper-65. Use these data to compute the average mass of natural copper. (The mass values for 63Cu and 65Cu are 62.93 amu and 64.93 amu, respectively.)

7. What is the atomic mass of if, out of every 100 atoms, 25 have a mass of 176 amu, 16 have a mass of 177 amu, 23 have a mass of 178 amu, 31 have a mass of 179 amu, and 5 have a mass of 180 amu?

8. Three occur in nature -- calculate the average atomic mass of argon to two decimal places, given the following relative atomic masses and abundances of each of the isotopes: argon-36 (35.97 amu; 0.337%), argon-38 (37.96 amu; 0.063%), and argon-40 (39.96 amu; 99.600%).

9. What is the atomic mass of if 78.99% of its atoms have a mass of 23.98 amu, 11.01% of its atoms have a mass of 24.98 amu, and 10.00% of its atoms have a mass of 25.98 amu?

6 10. Three isotopes of occur in nature. 92.23% occur as Silicon-28 (which has an atomic mass of 27.97693 amu); 4.68% occur as silicon-29 (which has and atomic mass of 28.97649 amu); and 3.09% occur as silicon-30 (which has and atomic mass of 29.97377 amu). Calculate the atomic weight of silicon.

11. CHALLENGE: There are only two isotopes of : Antimony-121 and Antimony-123. Calculate the percentage of each isotope if the average atomic mass of Antimony is 121.76 amu.

LT 4: I can calculate molar conversion problems.

Practice Problems:

1. Describe a mole (use, size, etc).

Moles and grams

2. 100 g of NaOH = ? moles of NaOH

3. 3.5 moles of CO2 = ? grams of CO2

4. 650 g of H2O = ? moles of H2O

Grams to moles = ______by molar mass

Moles to grams = ______by molar mass

7 Moles and molecules

5. 4.25 x 1027 molecules CO = ? moles of CO

6. 1.28 x 108 mol PbBr4 = ? molecules of PbB4

7. 1.2 x 1020 molecules SnO = ? moles SnO

Molecules to moles = ______by 6.022 X 1023

Moles to molecules = ______by 6.022 X 1023

Molecules/Formula Units to Atoms

8. 3.0 X 1015 molecules of C6H12O6 = ? atoms of C

9. 9.03 X 1024 atoms of Br2 = ? molecules of Br2

10. 2.3 X 1025 formula units of NaCl = ? atoms (total atoms)

Atoms to Molecules/Formula Units = ______by subscript of element(s)

Molecules/Formula Units to Atoms = ______by subscript of element(s)

Mixed Questions

11. Convert the following:

A) 36.03 g C →? atoms C

B) 2.408 X 1024 formula units NaCl → ? g NaCl

8 C) .25 moles H2O →? g H2O

D) 12.67 moles C6H12O6 →? molecules C6H12O6

E) 1000 g Cl2 → ? molecules Cl2

F) 3.01 X 1025 atoms of Au → ? grams Au

G) 4.2 X 1022 molecules of NO2 → ? grams of NO2

12. What is the mass in grams of 2.52 moles of , Fe?

13. How many moles of , Ca, are in 0.565 g of calcium?

14. How many molecules of H2O, water, are in 3.75 moles of water?

15. What is the mass in grams of 5.7 x 1015 atoms of chloride, NaCl?

16. How many atoms of , S, are in 3.00 g of sulfur?

9 LT 5: I can identify, describe and write the nuclear equations for alpha, beta, gamma and neutron decay; I can compare fission and fusion reactions and applications of each.

Practice Problems:

1. What is a nuclear reaction? What determines the stability of the nuclide?

2. What is the neutron-proton ratio among elements with low atomic numbers? High atomic number?

3. What is the difference between ionizing and non-ionizing radiation?

4. Define

5. Complete the following table:

Type of Symbol Change in Mass # Change in Atomic # Penetrating Strength Radiation Alpha

Beta -

Beta +

Gamma

6. Complete the following nuclear decay equations:

A. 22286Rn → ______+ 42He E. 146C → ______+ 0-1

B. 8737Rb → 8738Sr + ______F. 9943Tc → ______+ 

263 259 13 13 C. 106Sg → 104 Rf + ______G. 7N → 6C + ______

D. 116C → ______+ 0+1 H. 10646Pd + ____ → 10645Rh

7. Write the nuclear equation and predict the isotopes produced for the following:

A. Th-234 releases one 0+1 particle B. U-238 releases one 42He particle

8. Write a nuclear equation for the of -231.

10 9. Write a nuclear equation for the positron/beta positive decay of nitrogen-13.

10. Write a nuclear equation for the beta negative decay of -223.

11. Write a nuclear equation for the alpha decay of -150.

12. Uranium-235 decays by the following series. Write the final stable isotope.

235 92U → ,,,,,,,,,, → ______

13. Predict the daughter species when the parent species undergoes alpha decay. Write the decay equation. Np-238 →

14. Predict the daughter species when the parent species undergoes beta negative decay. Write the decay equation. Th-234 →

15. Complete the continuing radioactive decay for the following radioactive isotope:

Alpha → Beta - → Alpha → Gamma 235 92 U → _____ → _____ → _____ → _____

16. Show the breakdown of the following isotopes being hit by one neutron: A. U-235 to Ba-142 and Kr-92

B. U-235 to Rb-90 and Cs-144

C. U-238 to Xe-142 and Sr-92

17. Show the breakdown of the following radioactive isotope being hit by one neutron. U-238 + Neutron → Ba-141 and Kr-90

11 18. Create a Venn diagram comparing and contrasting nuclear fission and nuclear fusion reactions. (Include the following: examples of each, similarities, and differences.)

CCRS Scores: CCRS #1 (productivity): SC DV BG CCRS #2 (collaboration): SC DV BG

CCRS #3 (feedback): SC DV BG CCRS #4 (respect): SC DV BG

Choose one CCRS standard and write one sentence explaining how you can improve (even if you are secure). 12