instructor: nicole stevens 1 of 8 winter 2008 …emp.byui.edu/stevensn/exam1key.pdfinstructor:...

Instructor: Nicole Stevens 1 of 8 Winter 2008

1. Which of the following is a chemical property?

a. density d. boiling point

b. color e. odor

c. reactivity with water f. all of these are chemical properties

2. Which measurement below is equivalent to 15.5 kilograms?

a. 155 g d. 0.0155 g

b. 1.55 x 107 mg e. 1,550 g

c. 1.55 x 105 g f. 15,500 mg

3. Which of the following is a chemical change?

a. burning a piece of paper d. wadding up a piece of paper

b. water boiling e. melting gold

c. ice melting f. pouring water from a pitcher to a cup

4. Refer to the Periodic Table. Which of the following elements is a metalloid?

a. calcium d. magnesium

b. aluminum e. oxygen

c. copper f. silicon

5. Which of the following is true of isotopes?

a. they have the same number of protons, but different number of electrons

b. they have different numbers of protons and neutrons, but similar physical properties

c. they have the same number of neutrons, but different number of protons

d. they have the same number of protons, but different number of neutrons

e. they have the same number of neutrons, but different number of electrons

6. Which is the correct electron configuration of a non-metal?

a. 1s12s

23s

34s

4

b. 1s22s

22p

63s

2

c. 1s22s

22p

63s

23p

5

d. 1s22s

22p

63s

23p

64s

23d

4

e. 1s22s

22p

63s

23p

64s

1

7. Which can hold the fewest electrons?

a. energy level 3 d. a "d" energy sublevel

b. a "p" energy sublevel e. a "d" orbital

c. energy level 2 f. energy level 4

8. What is the molar mass of magnesium bromate?

a. 134.84 g/mol d. 264.11 g/mol

b. 104.21 g/mol e. 280.11 g/mol

c. 152.21 g/mol f. 83.11 g/mol

9. What is the formula mass of strontium chlorite?

a. 222.52 g/mol d. 222.52 amu

b. 123.07 amu e. 123.07 g/mol

c. 155.07 g/mol f. 171.07 amu

Chemistry 100 Exam 1

Part 1: Multiple ChoiceYou may write on this test, but MARK YOUR FINAL ANSWERS on a separate bubble sheet.


Match each of the following scientists with the scientific research they did.

10. Rutherford a. Wrote The Sceptical Chymist in 1661

b. Discovered ions, realized atoms were electrical in nature

11. Schrodinger c. Organized elements into the Periodic Table

d. Coined term "electrons" based on work with cathode-ray tubes

12. Thomson e. Law of Conservation of Mass

f. "Electron cloud" surrounds nucleus, region of probability

g. Proposed an encompassing "atomic theory"

h. Gold-foil experiment suggested atomic structure

i. Oil drop experiment calculated mass of electrons

13. How many molecules of carbon dioxide are present in 1.5 moles of carbon dioxide?

a. 1.5 molecule d. 6.022 x 1023

molecules

b. 66 molecules e. 9.03 x 1023

molecules

c. 44.01 molecules f. impossible to tell from given information

14. Which atom produces a cation when ionized?

a. Al d. S

b. O e. He

c. P f. all of the above produce anions

Match the following to its correct name.

a. phosphorus dioxide

15. PO23-

b. hypophosphate ion

c. sodium sulfate

16. NO3 d. disodium sulfate

e. disodium sulfur trioxide

17. Na2SO3 f. nitrate ion

g. phosphite ion

h. sodium sulfite

i. hypophosphite ion

j. nitrogen trioxide

Match the following to its correct formula.

18. Nickel (II) chloride a. Mg3PO2 f. NiCl2

b. Ni2Cl g. Ni2ClO2

19. Magnesium phosphide c. Al3(NO2) h. Mg2P3

d. Mg3P2 i. AlN3

20. Aluminum hyponitrite e. Al(NO)3 j. AlNO3

21. What is the correct formula for ammonium carbonite?

a. (NH3)2CO2 d. Am2CO2 g. NH4CO2

b. (NH4)2CO2 e. Al2CO2 h. NH3CO2

c. (NH3)2CO3 f. Al2(CO2)3 i. NH4CO4

Part 1: Multiple ChoiceMARK YOUR FINAL ANSWERS on a separate bubble sheet.



22. A linear VSEPR molecular shape is characteristic of which of the following?

SO22-

H2O SO2 NO2- CO2

A. B. C. D. E.

a. A e. E i. C and E

b. B f. A and C j. all of the above

c. C g. A and D

d. D h. A, B and D

23. What is the term that means an an average of all an element's isotopes?

a. polarity d. molecular shape

b. mass number e. electronegativity

c. atomic number f. atomic mass

24. A chlorine atom has gained one electron. Which of the following is NOT true about the atom now?

a. it is an anion d. it has the same electron configuration as argon

b. its mass number increases e. it would be attracted to positive ions and form ionic bonds

c. it carries a -1 charge f. all of the above are true

25. Sodium reacts with chlorine gas to form table salt (sodium chloride). In the balanced equation, what are the

coefficients in front of sodium and chlorine gas, respectively?

a. 3 and 3 d. 3 and 2

b. 2 and 3 e. 3 and 1

c. 2 and 1 f. 1 and 1

Indicate whether the following statements are true or false. a. TRUE

b. FALSE

26. The subscripts in a molecular formula represent proportions or ratios of moles.

27. One mole of water contains the same number of molecules as one mole of carbon dioxide.

28. An s-orbital in energy level 1 has both the same shape and the same volume as an s-orbital in energy level 3.

29. Alkaline earth metals react more vigorously with water than alkali metals.

30. p-orbitals are dumbell shaped, while s-orbitals are spherical.

You may write on this test, but MARK YOUR FINAL ANSWERS on a separate bubble sheet.


Part 1: Multiple Choice


Name

I. Write the full electron configuration for each of the following elements in order of how the orbitals fill.

a. Copper

b. Krypton

II. If a piece of aluminum has a density of 1.73g/mL and a volume of 8.75mL, what is its mass?

(Answer to 2 decimal places)

III. Convert each of the following measurements into kilometers:

a. 1.75 x 109 mm

b. 1.45 m

IV. Write each of the following in scientific notation:

a. 564,000

b. 0.000523

The chemical symbol of the following elements is represented by "X". Refer to the following figures

for questions V - VII.

46 46 47 46 48

23 22 22 21 24

a. b. c. d. e.

V. Which of the above figures are isotopes of each other?

VI. Which of the above figures have the same number of neutrons?

VII. Figure (b) represents which element from the Periodic Table?

XX X X X

Chemistry 100 Exam 1Part 2 : Write-on

Please write your answers clearly in the space provided. SHOW ALL WORK!


Name

VIII. Consider a molecule of nitrogen trihydride (ammonia).

a. Draw the complete electron-dot configuration of nitrogen trihydride.

b. What is the VSEPR molecular shape of this molecule?

c. What is the intramolecular force for this molecule?

d. What is the intermolecular force for this molecule?

e. What state of matter is this compound most likely to be?

IX. Perform the following "Roadmap" calculations: (Answers to 2 decimal places)

a. How many grams of chromium are present in a sample that contains 3.25 x 1021

Cr atoms?

b. How many atoms of oxygen are present in 96.4g of aluminum sulfate?

c. How many grams of phosphorus are present in 49.7g of magnesium phosphite?




Name

X. Dihydrogen sulfide reacts with iron (III) perchlorate to form iron (III) sulfide and hydrogen perchlorate.

a. Write the balanced equation.

b. If I begin with 32.0g of iron (III) perchlorate, how many grams of hydrogen perchlorate will form?


c. If I want to form 60.0g of iron (III) sulfide, how many grams of dihydrogen sulfide to I need to react?


BONUS!! d. What state of matter is the dihydrogen sulfide most likely to be?

How can you tell?

e. What state of matter is the iron (III) sulfide most likely to be?

How can you tell?





Roadmap to Chemistry Mass

Calculations

Grams of

element

Molar mass

of element

(g/mol)

Moles of

element

Avogadro’s

number of

atoms or ions

Atoms or

Ions

Atomic mass

(amu / atom)

Amu of

element

Grams of

compound A

Molar mass of

compound A

Moles of

compound

A

Avogadro’s

number of

molecules

Molecules

Formula

mass (amu /

molecule)

Amu of

compound

Subscripts

in formula

Coefficients in

balanced

equation

Moles of

compound

B

Molar mass of

compound B

Grams of

compound B

instructor: nicole stevens 1 of 8 winter 2008 …emp.byui.edu/stevensn/exam1key.pdfinstructor:...

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