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  What is the density of asubstance with a mass of 45.00 g and a volume of 26.4 mL?



   

 

  1.70 g/mL


   

 

  0.59 g/mL


   

 

  0.587 g/mL


   

 

  45.0 g/mL


  




2 points  

QUESTION 9

  Which of the followingmatters is a compound?



   

 

  Copper


   

 

  Water


   

 

Saline solution


   

 

  Air


  




2 points  

QUESTION 10

  A dose of aspirin of 5.0milligram per kilogram has been prescribed to reduce the fever of an infantweighing 8.5 pounds.  The number of milligram of aspirin that should beadministered is



   

 

    53 mg


   

 

    19 mg


   

 

    1.6 mg


   

 

    5.0 mg


  




2 points  

QUESTION 11

  The number of valence shellelectrons in all noble gases (except helium) is



   

 

    6


   

 

    7


   

 

    8


   

 

    9


  




2 points  

QUESTION 12

  The number of electrons in aneutral atom with 30 protons and 34 neutrons is



   

 

    30


   

 

    64


   

 

    34


   

 

    94


  




2 points  

QUESTION 13

  How many electrons is in thevalence shell of a calcium atom?



   

 

    20


   

 

    8


   

 

    2


   

 

    1


  




2 points  

QUESTION 14

  How many protons, neutrons,and electrons are in the following isotope, respectively?



   

 

3, 3, 3


   

 

3, 6, 3


   

 

6, 3, 6


   

 

6, 3, 3


  




2 points  

QUESTION 15

  What is the ground state ofa hydrogen atom?



   

 

  Threeelectrons in the n=1 level


   

 

  Oneelectron in the n=2 level


   

 

  Oneelectron in the n=1 level


   

 

  Oneelectron in the n=1 level and one electron in the n=2 level


  




2 points  

QUESTION 16

  Which substance would bepresent in the greatest concentration during the morning rush hour on asmoggy day in Los Angeles?



   

 

    NO


   

 

    O3


   

 

    NO2


   

 

    SO3


  




2 points  

QUESTION 17

  When coal and fuel oil areburned, what two primary pollutants are formed?



   

 

  SO2and CO2


   

 

  HNO3and H2SO4


   

 

  COand O3


   

 

  Hydrocarbonsand NO2


  




2 points  

QUESTION 18

  Why are small particulatesin the atmosphere dangerous to human beings?



   

 

  Theycan enter into and lodge in very small crevices of the lungs and causeconcentrated abrasive injury.


   

 

  Theygrind the enamel off of teeth.


   

 

  Theyabsorb and concentrate other pollutants.


   

 

  Theydissolve in rivers and lakes and fill them up.


  




2 points  

QUESTION 19

  Convert 0.000053% to ppb



   

 

  53 ppb


   

 

  530 ppb


   

 

  5300 ppb


   

 

  5.3 ppb


  




2 points  

QUESTION 20

  Magnesium nitride is made upof magnesium ions and nitride ions. What is the expected formula of magnesiumnitride?



   

 

  MgN


   

 

  Mg2N3


   

 

  MgN2


   

 

  Mg3N2


  




2 points  

QUESTION 21

  How many nonbondingelectrons are in the water molecule?



   

 

    0


   

 

    2


   

 

    4


   

 

    6


  




2 points  

QUESTION 22

  How many nonbondingelectrons are in the water molecule?



   

 

    0


   

 

    2


   

 

    4


   

 

    6


  




2 points  

QUESTION 23

  Which of the followingsubstances has polar covalent bonds?



   

 

  CaF2


   

 

  KBr


   

 

  NH3


 

   

 

  CH4


  




2 points  

QUESTION 24

  What is the charge on an ionwith 7 protons, 7 neutrons, and 10 electrons?



   

 

    0


   

 

    +3


   

 

    -3


   

 

    -7


  




2 points  

QUESTION 25

  How are carbon dioxideconcentrations determined from thousands of years ago?



   

 

  Analysisof decayed plant material


   

 

  Analysisof ice samples


   

 

  Analysisof the atmosphere


   

 

  Analysisof the Earth’s core


  




2 points  

QUESTION 26

  The highest recordedtemperature on earth was 136°F in El Azizia, Libya. What is this temperaturein Celsius?



   

 

104 °C


   

 

277 °C


   

 

58 °C


   

 

76 °C


  




2 points  

QUESTION 27

  How much energy is in agamma ray with a frequency of 2.5 x 1020 s-1 (E = hvwhere h = 1.58 x 10-34 cal • s)



   

 

4.0 x 1020 cal


   

 

4.0 x 1054 cal


   

 

4.0 x 10-20 cal


   

 

4.0 x 10-14 cal


  




2 points  

QUESTION 28

  What is the problem withincreasing amounts of carbon dioxide in the atmosphere?



   

 

  Itslack of consumption in respiration


   

 

  Arise in pH of ocean water


   

 

  Toomuch UV radiation being absorbed


   

 

  Globalwarming


  




2 points  

QUESTION 29

  What chemical bond is brokenby a photon of light in a typical CFC molecule?



   

 

    C-H


   

 

    Cl-Cl


   

 

    H-Cl


   

 

    C-Cl


  




2 points  

QUESTION 30

  Which type of chemical bondrequires the least amount of energy to break?



   

 

  Single


   

 

    Double


   

 

  Triple


   

 

  Quadruple


  




2 points  

QUESTION 31

  Approximately how many ozonemolecules can one chlorine atom derived from one CFC molecule react with?



   

 

  1 molecule O3


   

 

  100 moleculesO3


   

 

  1000 moleculesO3


   

 

  100000molecules O3


  




2 points  

QUESTION 32

  Which of the followingexplains why CFCs are not removed from the atmosphere by rainout?



   

 

  CFCsare not water solublen water.


   

 

  CFCsare chemically inactive in the troposphere


   

 

  UVradiation removes them more quickly.


 

 

   

 

  Thisis due to both their chemical stability and solubility in water.


  




2 points  

QUESTION 33

  Which will have the largestmolar mass?



   

 

  1mole of Ar, argon


   

 

  1mole of CO, carbon monoxide


   

 

  1mole of N2, nitrogen


   

 

  1mole of Sn, tin


  




2 points  

QUESTION 34

  What numbers are needed tobalance the following equation, respectively?  ____CO2 + ____H2O —>____C6H12O6 + ____O2



   

 

1, 1, 1, 1


   

 

6, 6, 6, 6


   

 

6, 6, 1, 6


   

 

6, 1, 1, 6


  




2 points  

QUESTION 35

  How many atoms arerepresented in the formula Ca3(PO4)2?



   

 

    9


   

 

    11


   

 

    13


   

 

    1


  




2 points  

QUESTION 36

  What is the number of atomsin 1.0 mol of nitrogen dioxide, NO2?



   

 

1.8 x 1024 atoms


   

 

1.8 x 1023 atoms


   

 

2.0 x 1023 atoms


   

 

  3atoms


  




2 points  

QUESTION 37

  The balanced equation forthe decomposition of hydrogen peroxide, H2O2, is givenbelow. What number of grams of O2 result from 3 . g of hydrogenperoxide?



   

 

300. g O2


   

 

3 . g O2


   

 

320. g O2


   

 

338. g O2


  




2 points  

QUESTION 38

  The strength of an acid isrelated to its



   

 

  Extentof ionization


   

 

  Reactionwith a salt


   

 

  Concentration


   

 

  Commercialranking in the economy


  




2 points  

QUESTION 39

  What volume (in liters) of 1M NaOH contains g sodium hydroxide?



   

 

  100 L


   

 

  1 L


   

 

  10 L


   

 

  1000 L


  




2 points  

QUESTION 40

  What is the pH of a 0.0001 MHCl solution?



   

 

  10-4


   

 

  0.0001


   

 

  -4


 

 

   

 

  4


  




2 points  

QUESTION 41

  What is the salt formed whenan HCl solution reacts with Mg(OH)2?



   

 

  MgCl2


   

 

  Mg2Cl


   

 

  MgCl


   

 

  Mg2Cl2


  




2 points  

QUESTION 42

  How many moles of sulfuricacid, H2SO4(aq) are in 2.0 liters of 18 M H2SO4?



   

 

    9.0 mol


   

 

    20. mol


   

 

    36 mol


   

 

    98 mol


  




2 points  

QUESTION 43

  In the equation 2 Na(s) + Cl2(g)—> 2 Na+ + 2 Cl–, the oxidizing agent is



   

 

    Na (s)


   

 

    Cl2 (g)


   

 

    Na+


   

 

    Cl-


  




2 points  

QUESTION 44

  Identify the reduced speciesin the following equation CH4(g) + 2O2(g) —> CO2(g)+ 2H2O(g)



   

 

   

 

   

 

   

 

  




2 points  

QUESTION 45

  In an electrolysis reaction,oxidation occurs at which electrode?



   

 

    Cathode


   

 

  Anode


   

 

  Bothelectrodes


   

 

  Neitherelectrode


  




2 points  

QUESTION 46

  Which of the following is afree radical?



   

 

  Ozone,O3


   

 

  Fluorine,F2


   

 

  Chlorine,Cl2


   

 

  Nitrogendioxide, NO2


  




2 points  

QUESTION 47

  How much heat is required toheat 25 g of liquid water from 20 °C to 100 °C



   

 

    25 cal


   

 

    1000 cal


   

 

    2000 cal


   

 

    1  00 cal


  




2 points  

QUESTION 48

  The phrase “acidrain” applies to rain water with a pH of



   

 

    7


   

 

    6-7


   

 

    < 5.6


 

 

   

 

    5.6


  




2 points  

QUESTION 49

  Identify the exothermicprocess among the following.



   

 

  Woodburning


   

 

  Boilingwater


   

 

  Meltingice


   

 

  100cal of energy are absorbed


  




2 points  

QUESTION 50

  Fertilizers such as nitratesand phosphates are examples of what type of pollutant?



   

 

  Mineralsand chemicals


   

 

  Infectiousagents


   

 

  Plantnutrients


   

 

  Oxygen-demandingwastes


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