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Chern 1150 Section 004 Fall 2011 Exam 1 Name
Instructions:
- Put your name on the front of this exam.
2. Answer all the questions in this exam to the best of your abilities. Keep in mind that there
may be multiple correct answers on some multiple choice problems. To receive full credit on multiple choice problems, identify all correct answers.
- On mathematical problems, you have to show your work to receive full credit. If you do not show your work including unit cancellation, etc., you will receive very little credit for the problem.
- You will also be graded on reporting your answer with the correct significant figures and units. Please circle your fmal answer for mathematical type problems.
The following information might be of use:
1.0000 year = 365.24 days
1.0000 day == 24.000 hours
1.0000 hour = 60.000 minute
1.0000 min = 60.000 seconds
1.0000 pound (lb) == 453.59 grams
r: 1.0000 mL^ =^ 1.0000 crrr'
2.5400 em == 1.0000 inch
1.0000 foot == 12.000 inches
- (44 pts) Fill in the blanks for the following sentences: Ol ph eec...
Chemistry is a scientific discipline that seeks to understand the behavior of "h Ct \t er by
studying O•.:\1:>WV.s and C 0 M..~t>v~Js.
VV\ 0 \ e cedes) e+r. The main difference between a "soft" science like philosophy and a "hard" science like physics or chemistry is that hard sciences are based on ~M.~ i r ic.J. -e vC~c. e.) e h..
The different states of matter are SO\ la dc...~
_..:...!\ l+tJ.}-.::'"..:...:..:id~ __ , and
state of matter can be compressed with pressure.
A solution that is the same throughout is termed ht> V\l'\O{}e.tI.eOUS different phases in contact is called h'e:..e.~ 6 12A"-e 0",,",.
while one that has
Atoms are particles consisting of-f fD-t:>Y~ , \1\ e~k~ ,and e. I~ c...fvofl.f.
--,-e_vo=--h_lIl_'s and -----'n'---'--'f.~I,A,"=+vv____=oI.s make up the core of the atom.
'P ro1-D"y"s are positively charged and ..e... ( e..c h-o".f charged particles that make up an atom.
are negatively
The atom is mostly ~ e:bt space and consists of a central -,v'\L..L.l\A."",,"C,,-,t-,-f.M,!~,---- surro:IJifd by I{< Ie.c...fvo ~ very far away.
. A charged atom is called a(n) IO~. If this is positively charged it is called a(n) C odi"'- , while if it is negatively charged, it is called , a(n) ~V.\o'.
- (2 pts) Which prefix denotes 1 x 10-^9 of a unit in SI units?
- (4 pts) Convert 14 kilometers into nanometers. Ix(oq ""~ (^) ;>
l~~XIO y~
~ l f-l- ('4\c. ~~If.)
looo~ X 1..--.
- (4 pts) A rock that has a mass of 17.24 g displaces 8.23 mL of water when it is dropped into a flask. What is the density of the rock?
cf:; ;Iv 1'1.2-t.f~_^ ~ 8 .J.-£ t""L
9. (5 pts) Convert the density you found in the previous problem to lbs per fr'.
\ \l:> ~ lb. q ~ ~2~/_
;(.0^ PI I^ Cfjcl ~:; L^ ;).^ D~-^ X - c »c^ l ~)('^ {' V X^ YI
~-,..er rvlL^ J.{'J3.'5"1'~^ Y" 5'"<""<.
'- --------r-------------~~ -- 'tf~ 1O. (4 pts) How many years are 25.25 nanoseconds?
I~/ ~ \ ~ \ ~ ~~ ~ X X I ON,'L )(' '-f L.? X .3"'5 .2-~ .,(~ - os. ~ t~lo.~E -Z-1O^7 2..-/·_
_r -.-/ /<J
3"h.
- (4 pts) What is the answer to 784.53 x 1204.66 x (l08.55 -14.2)? "'-I
)( Q1·Lf
~ & s..c.
8.<1.;}.}<{
-J~ 8.00) ~ID jV" ~
lp+"
! OM..2. SO'-+
t!>~ \ d~0.. o.f
si~ ~~t ;, 3f'n (^8) QJ1. 00)0 00
\ r+.
- (6 pts) How many gallons is 1.45 x 10^6 nanograms of ethanol? Density of ethanol = 0.789 g/cm";
1 gallon = 3785 mL; 1 cnr' = 1 mL
lc/
~ X \X10}a
- (2 pts.) Which of the following statements is not part of the atomic theory? a. Elements are composed of tiny, indestructible atoms. b. Atoms of one particular element have a distinct mass from those of another. c. Atoms combine in whole number ratios to form compounds. d. Atoms of one element cannot change into atoms of another. ·BIn a chemical reaction, atoms only rearrange how they are grouped with other atoms, and they change their identity.
- (3 pts) a. Identify the following element: Z = 35
b. How many neutrons does the element have in this problem if A = 81? B-r A~ ~
c. Provide the correct name for the isotope in this problem.
Y::
- (2 pts) What charge will magnesium have if it becomes an ion?
- (4 pts) A compound can be made between magnesium and nitrogen. a. What is the molecular formula for this compound? ~ 4-'2-. N-~
)!^ * j ::..·t-4. X i-, L. ~^ -".^ ~~'1^ 0.;;) N.1-^ ~r+-
b. What would the name of this compound be?
- (7 pts) Name the following ions or compounds: a. CU(N03)2 Co r r-er ( ( I) n', ,~,k..
b. NH/
nl,~k- f. CN- Cd A.1\·\tl~
g. N 20 S
d1~'M>~f~'~~'" id ~
\ p+ Ie fA. •
a. (2 pts) What is the name of the compound consisting ofb and e from the previous problem? _a.~~oV\iv"",- t_ f·k·k...
b. (2 pts) What is the formula ofthe compound? N.'1NO~
c. (2 pts) What is the molar mass of the compound? I\j ){ 1- X IfoCl; z: 280 ql...l NX.Lf X 1.008:- 't. c;52-. 90 ~o'S" Si~ o )( 3 X 1lr,.iO ~ *1- -r. (^) CO
d. (5 pts) What is the mass percent of nitrogen in the compound?
tt~ e. (5 pts) How many g of nitrogen are there in 15.24 g of the compound? -- ".•.. --~
= c[3^3 'fJ ~
2-~, 01. uJ~
~O.OS-8/~
- (5 pts) Identify the name or molecular formula the following acids: a. HeI: ~JclroddonL e c ~~ b. HN02: Y\i~\i\J ~c.rd c. hydrobromic: U ~'('""" d. sulfuric: ~2.-~0'l e. carbonic: Hz.-c OJ
Score: ---l/
Chern 1150 Section 004 Fall 2011 Exam 1 Name^ Yu^ 2- ~~
Instructions:
- Put your name on the front of this exam.
- Answer all the questions in this exam to the best of your abilities. Keep in mind that there may be multiple correct answers on some multiple choice problems. To receive full credit on multiple choice problems, identify all correct answers.
- On mathematical problems, you have to show your work to receive full credit. If you do not show your work including unit cancellation, etc., you will receive very little credit for the problem.
- You will also be graded on reporting your answer with the correct significant figures and units. Please circle your fmal answer for mathematical type problems.
The following information might be of use:
1.0000 year = 365.24 days
1.0000 day = 24.000 hours
1.0000 hour = 60.000 minute
1.0000 min = 60.000 seconds
1.0000 pound (lb) = 453.59 grams
1.0000 mL = 1.0000 cnr'
1.0000 foot = 12.000 inches
(;2.5'1 c-}f ~
\ ~.~ ~ z:
I b. f 2.5400 em = 1.0000 inch
- (2 pts) Identify any pure compounds from the choices below: ;L fl-- e c. G)water b. helium ® nitrogen dioxide d. hydrogen e. neon
f. Pepsi Cola
® magnesium sulfate ([) sodium chloride in a salt shaker i. sodium chloride in water
- (2 pts) Identify any physical changes from the choices below: fa:) Boiling of water Y. burning of gasoline c. iron binding with oxygen forming rust @ dry ice evaporating e. water and carbon dioxide reacting to form sugar C9water and carbon dioxide mixing in air
- (2 pts) Identify any chemical changes from the choices below: (a') rusting of metal (E) sodium and chlorine forming NaCI c. sugar dissolving in water d. sugar melting e. gasoline evaporating f. compressing gas ® exploding hydrogen
- (2 pts) Identify any units of mass from the choices below: Q gram ~kilogram c. kilometer @ pound e. liter f. meter (j) nanogram h. yard
5.-9. -l i~
\1.1)+ t:.~
6. (2 pts) Which prefix denotes 1 x 10-6 ofa unit in SI units? --
- (4 pts) Convert 17 kilometers into micrometers.
I" ~ (L' '7x (0 ~\t:..ll»n •••....
~'A l~ + lA.- I'. I -r-:J'
- (4 pts) A rock that has a mass of25.24 g displaces 10.23 mL of water when it is dropped into a^ ---- flask. What is the density of the rock?
d :;.tn/V - .'J.:S. 2-ih~
3pb
- (4 pts) How many years are 42.25 microseconds? \ ~ \ ~"'
1.2.·).5" Mt'c.. ros X - ^ 'X <"0~t.tSX
9. (5 pts) Convert the density you found in the previous problem to lbs per fe. 3. y-
, /' 1. •• / t _,11.YX/tlA1_ 0» ~L.. J..'5~~ 1... 'l~~ ~.t?3)1:::'~ ..., .- - X ')(" r. .J IV )()r iY
~
is: .s !)'i. ,~ .ctl ~-. --'/
___^ \ \v--^ x-). \ ~()-^ !.9r^ I-::. ')< ,'0•...).-. '2-'1 ~.("S .3~5'~,l.'f"(J
~ OJ _I'l.
1~33~Xlby
.3~
- (4 pts) What is the answer to 74.530 x 124.667 x (108.554 -14.23)? '-../ 'V . '1,q,.'1 )( ''1.31.
o, cl v..~ o.-bov.J S~~ -PiJ!;"
3f.
glh~ Db or ~.1bt X 1"0 S-
\ y+.
- We have 3.520 grams of aluminum. a. (5 pts) Convert this to moles:
b. (5 pts) How many atoms is present in this amount of aluminum?
x (^) -
- (6 pts) How many grams is 9285 atoms of zinc (Zn)?
t "'~
q2-8'''-~S ~ x: ".OU.XI^021 evh-s X
, 6'.31; , ; "'" c.-t
1 "DoB" I 0'" ~
~ ('fL., !)~
- (2 pts) Identify which of the following compounds (or ions) are bound together with ionic bonds. a. S b. N0 3 C. CH 4 d. CgH,g
@FeCh
(!) BaS0 4
g. sol
- (2 pts) Which of the following will be a molecule in its elemental form? a. Na <::!9 S CPO (!)CI e. Ne
f. Fe
g. Zn
- (4 pts) A compound can be made between calcium and nitrogen. a. What is the molecular formula for this compound? Cv.-l.-+- f\J3- )(~ xz.
~+'" ~b
b. What would the name of this compound be?
- (7 pts) Name the following ions or compounds:
a. Fe(N03)2 ll~1. (\0 Y\ i-+v",-k
C. CI0 4 ' f e,..r (...k h>,.- 1'0.,.4-(_
d. S032• ~ v.,..f.-k-
e. N0 2 ' ni tv~-k-
- (6 pts) Caffeine consists of four atoms: Carbon, Hydrogen, Nitrogen, and Oxygen. What is the empirical formula of caffeine given the following mass percent composition: C 49.48%, H 5.19%, N 28.85%, 0 16.48%?
'b ph.
t hcU\ -h
show Ib.{-tO~ 0 x ~
SD~ 0 ~
~~J(,..,+- c-~..s ..J..o ~+ r ~_la,. +r 25. (4 pts) If the actual molecular mass of caffeine is 194.19 g/mol, what is the molecular formula?
~9.q8a c. X
5, \ ~ d H
i/ 1- ex It .;;;;..W,o~ ~)< f+ y.1·oOO' ;:; 5,~1'
2. ,c' N /- Iii .vl ':.lS~'
l x 0 "f. 1(, "OJ ~ 1(,·
1 L .u\ca
X .8 :;. I. IX'I~} ')~ X .~~- - :J.. 0 .5.~ I~ tV
It·vld-"
l.o)~O
£rh^ #
t 'J'j( c, /J!jN2.-
~~cl to sk~""" "",000' ~ w~
__ ---:c", '-'_,
""'0\ett.... t,."..- tvk."('" i ~ i-' ~ r. -Co~ ""l.... ) -e-
Score: ...J/1SO
2
