AP Chemistry Unit 11Denise DeMartino AP Chemistry --Unit 1 In
Class Problems 1.Figure I shows a glass cylinder containing four
liquids each of different density.Two of the liquids have been
identified.A table containing a list of substances and their
density (at 25 C) has been provided.From the list select a
substance for Liquid #1 and Liquid #3.Briefly explain the reason(s)
for your selections and for the remaining substances the reason
they were not selected. SubstanceDensity (gmL) Mercury13.5 Water1.0
Hexane0.660 Ethyl alcohol0.789 Dichloromethane1.33 Aluminum2.699
Bromine2.928 Gold19.3 2a.Compare and contrast accuracy and
precision. b)Which set(s) of measurements are precise? c)Which
set(s) of measurements are accurate? d)Which set(s) of measurements
are both precise and accurate? 3a.Explain the difference between an
exact number and an inexact number. b)For each case, indicate
whether the result is an exact or inexact number. (i)The number of
faces: (ii)The mass of six apples(iii)The number of seeds in the
apples in (a)(iv)The number of feet in one mile(v)The number of
liters in five quarts AP Chemistry Unit 12Denise DeMartino
4.Complete the following calculations and record the result using
the correct number of significant figures. Answer to correct number
Calculationof significant figures 0.347 0.0732 23.436 + 82.2 (8.25
x 0.14) 0.83412.45 (6.536 6.476)99.003 + 2.0915.The density of
concentrated sulfuric acid is 1.84 g/mL.Concentrated sulfuric acid
is 95 % pure sulfuric acid.What volume of concentrated sulfuric
acid contains 100 g of pure sulfuric acid? 6.For each of the
separation techniques listed below, give an example of how the
technique is used to separate the components of a mixture.
a)Decantationb)Filtration AP Chemistry Unit 13Denise DeMartino
c)Evaporation d)Distillation e)Paper chromatography f)Liquid-solid
chromatography AP Chemistry Unit 14Denise DeMartino AP Chemistry
Unit 15Denise DeMartino 7.Each diagram (A - P) show a sample of
substances as viewed at the atomic level.Characterize the contents
of the container in terms of each of the following categories:
Category I.Homogeneous mixture, heterogeneous mixture or pure
substance Category II.Element(s), compound(s) or both Category
III.Solid, liquid, gas or combination of phases AP Chemistry Unit
16Denise DeMartino 8.Determine the number of kilograms in 115
pounds using 2 unit conversion factors. 9.The approximate volume of
water contained in the oceans of the world is 3.3 x 108
mi3.Determine the volume in km3. 10.Given the following elements
determine the number of electrons, protons and neutrons. a) 10947Ag
b) 2412Mg c) 2413Al d) 10747Ag+ AP Chemistry Unit 17Denise
DeMartino 11.a) Do the elements in the alkali metals group, the
alkaline earth metals group and the additional metals aluminum and
gallium form positive or negative ions?What is the normal ionic
charge for each group? b)Do the elements in the halogen group, and
the element oxygen form positive or negative ions (primarily)?What
is the normal ionic charge for each group? 12.NaCl CaBr2 K2SCu3N2
NOSO3 NO2 P4O10 N2O4 NF3 ___________ 13.Many familiar substances
have common, unsystematic names.In each of the following cases,
give the correct systematic name: a)saltpeter
(KNO3)__________________ b)soda ash (Na2Co3)__________________
c)lime (CaO)__________________ d)baking soda
(NaHCO3)__________________ e)lye (NaOH)__________________
f)muriatic acid (HCl)__________________ g)milk of magnesia
(Mg(OH)2)__________________ h)dry ice (CO2)__________________
i)ammonia (NH3)__________________ 14.Write the chemical formula of
each substance mentioned in the following word descriptions. a)Zinc
carbonate can be heated to form zinc oxide and carbon dioxide. b)On
treatment with hydrofloric acid, silicon dioxide forms silicon
tetrafluoride and water. c)Sulfur dioxide reacts with water to form
sulfurous acid. d)The substance hydrogen phosphide is commonly
called phosphine. e)Perchloric acid reacts with cadmium to form
cadmium (II) perchlorate. f)Vanadium (III) bromide is a colored
solid. AP Chemistry Unit 18Denise DeMartino 15)Practice naming
compounds given their formula and writing the formula of a compound
given its name. 16.NH4NO3NaCN KNO2BaSO4 Ca(ClO4)2 Hg2O CuCO3 NaHCO3
17. HCl (g)HClO HCl (aq)H2SO4 HClO4 H2SO3 H2CO3 H3PO4 18.Complete
the following table M, Molarm, Mass ofn, Moles ofN, Number of
atoms,FormulaMass gmolsample (g)sample (mol)molecules, or formula
units H2SO4 98.00.825 Cr2O39.63 x 1023 unknown56.80.476 Mo62.8 AP
Chemistry Unit 19Denise DeMartino 19.IsotopeRelative MassPer Cent
Abundance 20Ne19.992 u 90.92 21Ne20.994 u2.57 22Ne21.991 u8.82 Find
the avg atomic mass! 20.Two isotopes of chlorine exist in
nature.75.77% of chlorine is 35Cl with a mass of 34.96885 amu. What
is the mass of the other isotope of chlorine? 21.Determine the
percent composition of each element in Ni3(PO4)2. AP Chemistry Unit
110Denise DeMartino 22. Determine the empirical formula for a
compound which is 26.6 % potassium, 35.4 % chromium and 38.1 %
oxygen.The compound has a molecular weight of 294.2 g/mol.What is
the molecular formula? 23.Determine the amount of iodine produced
when 145 g of KI react with excess copper (II) chloride. 2CuCl2(s)
+ 4KI(s) 2CuI(s) + 4KCl(s) + I2(s) 24.In the reaction, 2C2H6(g) +
7O2(g) 4CO2(g)+ 6H2O(g) Determine the moles of CO2 and H2O formed
when 2.00 moles of ethane are reactedwith 10.0 moles of oxygen. AP
Chemistry Unit 111Denise DeMartino 25.Calculate the mass of calcium
nitride formed when 50.0 g of calcium react with 50.0 g of nitrogen
according to the reaction. 3Ca(s) + N2(g) Ca3N2(s) 26.A common
laboratory method for determination of arsenic is described in the
reaction, As2O3(aq) + 2I2(s) + 2H2O(l) As2O5(aq) + 4HI(aq) a)If
2.50 g of As2O3, 4.50 g of I2 and 4.00 g of H2O are mixed, and the
reaction proceeds to completion, which reactant is the limiting
reagent? b)Calculate the mass of As2O5 which is theoretically
possible. c)If only 1.80 g of As2O5 is actually produced, determine
the percent yield in the reaction. AP Chemistry Unit 112Denise
DeMartino 27.An industrial method for the production of elemental
zinc from its ore is to roast the crude ore in oxygen and then
react it with CO.The following reactions describe the chemical
process, 2ZnS(s) + 3O2(g) 2ZnO(s) + 2SO2(g) ZnO(s) + CO(g) Zn(s)
+CO2(g) A 10.0 kg sample of an ore containing ZnS was chemically
treated according to the reactions described above producing 2.85
kg of Zn.Determine the percentage of ZnS contained in the original
sample of the ore. 28.A 0.00300 g sample of napthalene, a compound
containing only carbon and hydrogen, was burned in excess oxygen to
give 0.0103 g of CO2.Determine the empirical formula of
napthalene.The formula weight of napthalene is 128 u, determine the
molecular formula. AP Chemistry Unit 113Denise DeMartino AP
Chemistry Unit 114Denise DeMartino AP Chemistry Unit 115Denise
DeMartino AP Chemistry Unit 116Denise DeMartino AP Chemistry Unit
117Denise DeMartino AP Chemistry Unit 118Denise DeMartino AP
Chemistry Unit 119Denise DeMartino