Chemistry 130 Exam #l-A September 25,2013

Lab Day and Time:I Name:

Instructions

1. Do not open the exam until you are told to start.

2. This exam is closed note and closed book. You are not allowed to use any outside materialwhile taking this exam.

3. Use the spaces provided to write down your answers. To receive full credit, you mustshow all work. Do not write answers on any other pieces of paper. If you need more room,write on the back of the exam and be sure to include a note describing where the work islocated.

4. When solving numerical problems, make sure you include the proper units in your finalanswer.

5. If a question asks for a response in sentence or paragraph form, make sure you respond inthat format.

6. Useful data for the exam and a periodic table are provided on the last page of the exam.Carefully tear out these sheets if you wish.

Page # Points possible Points awarded

2-6 57

7 23

8 17

Attendance 3

EC 2

Total 100

1

Chemistry 130 Exam #l-A September 25,2013

Multiple ChoiceUnless otherwise directed, choose the single best answer for each question. Please use thespace provided to do your calculations.

I. How many significant figures should be in the answer to the calculation shown below?

1.251xl0-3-7.310xl0-4_ \\ :2S\ )(\0~ -- D, 7~ \0 )(\03

3.067xl0-2

3l.0b/ )(\.01..

\ -3o .S20\OXtOc 3..Db)X\i::;)L

a. 1

~

. 2. 3. 4

e. 5,

(), O\(b'\ \S~

2. According to our discussion in c~s, ~ ?s~ £'pt}st stable building block of matter?

a. moleculeb. protonc. electron

d.

C)neutronatom

3. I was asked to report the mass of a sample of water in the proper SI units. What should theunits be?

a. g@)kg

c. mole

d. mgNone ofthe abovee.

4. Convert 89.3 nL to kL.

Ci) 8.93xIO-ll kLb. 8.93xIO-8 kLc. 8.93x107kLd. 8.93x1010 kLe. None of the above.

\~LlOJO L

5. The element in the upper right comer ofthe periodic table _

a. is a metalb. is a metalloidc. is an alkali metal

~ is a halogenViS a noble gas

2

Chemistry 130 Exam#l-A September 25,2013

6. Which of the following elements has physical and chemical properties most similar toChlorine?

a. Hb. Nec. Na

SBr

C'<::\M.erJ~ \11"\. ~ $-.'\r\<=-' 9:/0J,f~ Jo kv<:: ~,,,,,,,i'c.v-c~~u \~vct p"'~\'c.;;.l Pvlu ft"fh~~

7. How many total atoms are indicated by the formula and coefficient written below?

3CHCh

a. 3 3 oL 5 :::.-l~ cD·"""' 15b. 5 e. None of the above.c. 8

8. Express 305010 in the proper form of scientific notation.-_--:>

a. 3x105

b. 3.0501x10-5

c. 30501xlOl

d. 3.05010x105

(5) None of the above

~

S,OS<J\ XtO

9. How many significant figures are in the measurement below?

0.04010 em

a. 2b. 304

d. 56e.

10. How many significant figures should be in the answer to the calculation shown below?\

4.044+8.11+3.4+0.01-0.564= IS·O lI

a. 1~2(s}3

d. 4e. 5

3

Chemistry 130 Exam #l-A September 25, 2013

11. The output of a German precision ball bearing plant is 1.96631xl06 g of ball bearings per fivedays. If each ball bearing has a mass of 0.0113 g, how many ball bearings does the plant makein a single day?

a. 3.84 xI 05 ball bearingsb. 7.67xl04 ball bearings

~ 867 ball bearingsc.V 3.48x 107 ball bearingse. None of the above.

\ dz4 t \l')CC; ~\ ,\l~~~ 1.:> ~ ~.~, .-=-- . 1 s~ 1 o 0\\3({ -'-----~--~~~~~~12. How many significant figures should be in the answer to the calculation shown below?,

~ ;t'(; i~

GJ'-== -~--3-0J-

(~ 3,' ',dl XIO L,~,

3 tL\ ~ ~ \() 6.~\

16x 841.4716.300 =

~c. 3

d. 45e.

13. What element has 25 neutrons and a mass number equal to 47?

~Ip:::

-:::p +

- P d

2.1

a. Mnb. Agc. Hf

(DTie. None of the above.

14. Which of the following elements is an alkaline earth metal?

a. Scb. Cuc, AId. Nac3None of the above is an alkaline earth metal.

15. According to our discussion in class, we use the scientific method to help us study/understandchemistry. What is the first step when using the scientific method?

a. Generate a hypothesis.

c!>DeveloP a theory.c. Make an observation.

. Perform an experiment.e. None of the above.

4

Chemistry 130 Exam #l-A September 25,2013

Use the diagrams below to answer questions 16 through 18. In the diagrams, assume each ballrepresents a different element. The transition from box A to box B represents a sample of matter thathas undergone a change.

A B ...,e· • •• tb •••..~.

16. Under normal conditions (i.e. the temperature and pressure of the classroom right now), asample of matter is best represented by box B. How do the attractive forces of the particlescontained in this sample of matter compare to those of water particles under the sameconditions?

~ They are stronger than those of water particles.~ They are weaker than those of water particles.

c. They are similar in strength to those of water particles.

17. When the transition from box A to box B occurs, what happens?

(j) A physical change.b. A chemical change.c. A chemical and physical change.

18. According to our discussion in class, what type of matter is represented by diagram A?

a. pure elementb. pure compoundc. homogeneous mixture

cDe.

heterogeneous mixtureNone ofthe above.

19. A sample of matter has a density equal to 1.11 g/mL. What is the volume of a 3.00x 107 ugsample of this matter?

a. 33.3 mLb. 27.0 mLc. 31.1 mLd. 0.037 mLe. None of the above.

,21012; -i( l

5

Chemistry 130 Exam #l-A September 25,2013

20. Fill in the missing information into the table. (10 points)

Element Name Element Symbol

AvJ,' ,I\I\.VA'1 Sb

Cadmium ·CJT' Sn

\ \A.

Silver A~Argon Av

21. What is the absolute uncertainty of the number written below? (3 points)

1060 kL @ '-<. c)22. An atom forms a 2+ ion. If the ion has 38 electrons, what is the chemical symbol of the

ion? (2 points)C(,":J~L -= p - ,~ ~

:2 r: p - S:'~'"

v ~OIf the mass number ofthe ion is equal to 78, what is the elemental notation for the ion?(2 points)

,. "

23. On the left hand side of the arrow below, draw a picture of the potassium (K) atom.Assume the potassium has 18 neutrons. On the right hand side of the arrow, draw a pictureof the ion that potassium forms. In your diagrams, include the location and number of theprotons, neutrons, and electrons. Label the nucleus and make sure the relative sizes of theatom and ion are accurate. Underneath the ion, label it as a cation or anion. (6 points)

----~6

Chemistry 130 Exam #l-A September 25, 2013

24. In order to receive full credit for the questions below, you must show all of your work and usea vertical dashed line to show where the significant figures end in all calculated values. Youmust show a rounded and unrounded value for each answer and place a box around the finalanswers for each part.

While working in my backyard this weekend I found a meteorite! My chemist friends and Idropped everything and did some chemical analyses. One of the things we found was that themeteorite was composed of a pure element. In order to help us identify the composition of themeteorite, we tried to experimentally determine its density. When the meteorite was placed in1.2326xlO-3 rrr' of water contained in a graduated cylinder, the water level rose to a volume of1.862xlO-3 m3.

a.) What was the volume of the rock in m3? Make sure your answer is in the proper form ofscientific notation. (4 points). ~ ? . J.

--3 . ._-> ~ ) '1)\,~ (':2-'(,o ",,3. _ 1,232(, X \0 .jV'o C-=C 0, '2 ~ X\i) hO.b7.S~~X\03 (\ ~

\ -f!./ ~G." 'A.~ \ t.t X.l0 V\

b.) What is the volume of the meteorite in mL? You must show all work and use dimensionalanalysis to receive full credit. (5 points)

'~ C:. .~C;)~<)It.tKlO h '<.,. \ )(\0 0'''\ \ ML ._

\ ('"1'" l(y'") " [

G;2 S '\'-1 fV\L

;;2<\ V'LJc.) Ifthe meteorite has a mass of 3.083xlO-1 tons, what is the mass in grams? You must show

all work and use dimensional analysis to receive full credit. Express your answer in theproper form of scientific notation. (4 points)

f S~ :2 171b: \ :) X\O 5

[2,7:;;loj] .2.000 \~'S

Chemistry 130 Exam #l-B September 25,2013

I Name: Lab Day and Time:

Instructions1. Do not open the exam until you are told to start.

2. This exam is closed note and closed book. You are not allowed to use any outside materialwhile taking this exam.

3. Use the spaces provided to write down your answers. To receive full credit, you mustshow all work. Do not write answers on any other pieces of paper. If you need more room,write on the back of the exam and be sure to include a note describing where the work islocated.

4. When solving numerical problems, make sure you include the proper units in your finalanswer.

5. If a question asks for a response in sentence or paragraph form, make sure you respond inthat format.

6. Useful data for the exam and a periodic table are provided on the last page of the exam.Carefully tear out these sheets if you wish.

Page # Points possible Points awarded

2-6 57

7 17

8 23

Attendance 3

EC 2

Total 100

1

Chemistry 130 Exam #l-B September 25,2013

Multiple ChoiceUnless otherwise directed, choose the single best answer for each question. Please use thespace provided to do your calculations.

1. What element has 30 neutrons and a mass number equal to 53?

a. Znb. I(0v

d. Tie. None of the above.

fY'tt) t\: z: p + V)

5~ p·t 30f ~ s~-&:>

:23v

Use the diagrams below to answer questions 2 through 4. In the diagrams, assume each ball representsa different element. The transition from box A to box B represents a sample of matter that hasundergone a change.

•e··e>.···.~ ••• ce·

A B • • e>e·. ·.~ ...• • ce·2. Under normal conditions (i.e. the temperature and pressure of the classroom right now), a

sample of matter is best represented by box A. How do the attractive forces of the particlescontained in this sample of matter compare to those of water particles under the sameconditions?

a. They are stronger than those of water particles.b. They are weaker than those of water particles.o They are similar in strength to those of water particles.

3. When the transition from box A to box B occurs, what happens?

A physical change.A chemical change.

c. A chemical and physical change.

4. According to our discussion in class, what type of matter is represented by diagram B?

a. pure elementb. pure compoundc. homogeneous mixture

CDe.

heterogeneous mixtureNone of the above.

2

Chemistry 130 Exam #l-B September 25,2013

5. A sample of matter has a density equal to 1.11 g/mL. What is the volume ofa 3.00x107 ugsample of this matter?

A 33.3mLuY 27.0mLc. 31.1 mLd. 0.037 mLe. None of the above.

6. The output of a German precision ball bearing plant is 1.96631x1 06 g of ball bearings per fivedays. If each ball bearing has a mass of 0.0113 g, how many ball bearings does the plant makein a single day?

a. 3.84x105 ball bearingsb. 7.67x104 ball bearings

~ 867 ball bearingsc.v 3.48x 107 ball bearingse. None of the above.

7. How many significant figures should be in the answer to the calcu~ation shown below?

4.044+ 8.11 + 3.4 + 0.01- 0.564 =

a. 1b. 2

{§)3d. 4e. 5

8. Which of the following elements has physical and chemical properties most similar toLithium?

a. Hb. Nec9Na

d. SBre.

9. Which ofthe following elements is an alkali metal?

a. Scb. Cuc, Ald. Mg ~\~.J\(!) None of the above is an albdine earth metal.

3

Chemistry 130 Exam #l-B September 25, 2013

10. How many significant figures should be in the answer to the calculation shown below?l·:J. 4>.1, $~.L)' ~

16x841.4-d6.300= ~ :l'? \11~ = ~G

e.a. 5b. 4c. 3

21

11. How many significant figures should be in the answer to the calculation shown below?1.251xlO-3-7.310xlO-4 I\2S \ x:.\03 - 0.73 i0.( {~:3>

3.067xlO-2 2- -3i.C:6IK~0

\ -3O.S20;OKlU

a. 1

cb;d. 4e. 5

-2-'';)Ob ;}(tD

- O,();~t;;<;~ {-12. How many total atoms are indicated by the formula and coefficient written below?

a. 4/'\ 3lJ 12

d. 7None of the above.e.

13. According to our discussion in class, what is the simplest stable building block of matter?

a. moleculeb. protonc. electron

neutronatom

14. The element in the upper right corner of the periodic table _

a. is a metalb. is a metalloidc. is an alkali metal

~ is a halogenV is a noble gas

4

Chemistry 130 Exam #l-B September 25,2013

15. I was asked to report the mass of a sample of water in the proper SI units. What should theunits be?

&:>~gc. mole

d. mgNone of the abovee.

16. Convert 89.3 nL to kL.

@ 8.93xl0-11 kL 81\31 IIi l~Lb. 8.93 x10-8 kL ':::'-'~'-.L-+'--':'--;-c....--;J+-'\-:-''\.--::,"\,,:--:-;lL·-c. 8.93xl07 kL ,x. \.J /''- VVV rd. 8.93xl01O kLe. None of the above.

17. According to our discussion in class, we use the scientific method to help us study/understandchemistry. What is the first step when using the scientific method?

a. Generate a hypothesis.b. Develop a theory.

@) Make an observation.d. Perform an experiment.e. None of the above.

18. Express 305010 in the proper form of scientific notation.

a. 3xl05

b. 3.0501xl0-5

c. 30501xl0i

A 3.050l0xl05c.v None of the above

<3toSO\ ~\.0

19. How many significant figures are in the measurement below?

0.04010 em

a. 2b. 3

(94d. 5

6e.

5

Chemistry 130 Exam #l-B September 25, 2013

20. In order to receive full credit for the questions below, you must show all of your work and usea vertical dashed line to show where the significant figures end in all calculated values. Youmust show a rounded and unrounded value for each answer and place a box around the finalanswers for each part.

While working in my backyard this weekend I found a meteorite! My chemist friends and Idropped everything and did some chemical analyses. One ofthe things we found was that themeteorite was composed of a pure element. In order to help us identify the composition of themeteorite, we tried to experimentally determine its density. When the meteorite was placed in1.8601xlO-3 m3 of water contained in a graduated cylinder, the water level rose to a volume of2.262xlO-3 m3.

b.) What is the volume of the meteorite in mL? You must show all work and use dimensional\ analysis to receive full credit. (5 points) I

lJ -'1 '\ <0 '3 l u 'c) .-l \(:)~ It~ ~\.) ""' \ X\0 C'"" \V'\ --:: -,0 <-t • ( ) (t'\ Lt '1"'1

3 \Lh3

c.) If the meteorite has a mass of2.496xlO-2 tons, what is the mass in grams? You must showall work and use dimensional analysis to receive full credit. Express your answer in theproper form of scientific notation. (4 points)

- -2r Z:G~( xr?\' ~- '1, ') ~'11,'3'2- xl0 ~

C:<,2(' '- )(\.)") ]d.) What is the density of the meteorite in g/mL? (2 points), ~

O Z, '")r LA \ 32 X\ 0 <' .__ 'a. /- A. - Go. \ 1 ~ ,- SS~£i I'L'2 ....y("\ L

LfOLf l~ '" L C; , =s- ~ ,~ ~/"'LJe.) Besides the fact that we found a meteorite, based on the mfonnation given and calculated

above, why should we be excited about our discovery? (2 points)

\h\~ \) '01-0/ -c. ct~ ~V\ ''\'" 1 ~"' J iAc..Jh- I-ft- k~c- \e",C...,J--" \c.t eJ r ~e ~fC ~ fN'b~'J ~,~J ~ ~ v,€-c,../ ~~ l

Chemistry 130 Exam #l-B September 25,2013

21 Fll' h . fI t . t th t bl (10 . t)I mt e rmssmg in onna IOn m 0 e a e. pom s

Element Name Element Symbol

Iv"",s--~ W

-.)Copper c;

:i£% )[;;~ '\ 'c\~ Ir= .sr, \V~

Chromium Cv--Lithium Ll

22. On the left hand side of the arrow below, draw a picture of the phosphorus (P) atom.Assume the phophorus atom has 16 neutrons. On the right hand side of the arrow, draw apicture of the ion that phosphorus forms. In your diagrams, include the location andnumber of the protons, neutrons, and electrons. Label the nucleus and make sure therelative sizes of the atom and ion are accurate. Underneath the ion, la' tion oranion. (6 points)

\

~V\\OV\23. An atom forms a 3+ ion. If the ion has 25 electrons, what is the chemical symbol of the

ion? (2 points) Cjr'-c.v~e. = r - e: -~ = r- 2..~

..f> ::: ::2-yIf the mass number of the ion is equal to 55, what is the elemental notation for the ion?(2 points)

24. What is the absolute uncertainty of the number written below? (3 points)

43000 ern"r

[ Io~O cV'-\ 77