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Hey guys. I found this test from a previous SI leader. Ignore any questions that you haven’t heard of, as we may not have covered them in our class. The Key is posted on the SI website, which is also from a previous leader. Sorry for her bad handwriting.Good Luck. -Matt
CHEM 177 Final Exam ReviewSunday, December 13
6:00pm - 10:00pm
Content Time Length (mins)EXAM 1 6-6:20pm 20
5 min breakEXAM 2 6:25 to 7:00pm 35
5 min breakEXAM 3 7:05 to 8:05 pm 60
5 min breakEXAM 4 8:10 to 8:45pm 35
5 min breakEND OF SEMESTER CONTENT 8:50 to 9:10pm 20
5 min breakQ and A 9:15 to 10pm 45
EXAM 1:1,2,3
1) Which of the following is a physical property?a) Reactivityb) Solubilityc) Heat of combustiond) Half life
2) Which of the following is a chemical property?
a) Enthalpy of Fusionb) Hardnessc) Colord) Flammability
3) Which of the following is an intensive property?a) Melting pointb) Massc) Enthalpy of formationd) Volume
4) Which of the following is an extensive property?a) Densityb) Molarityc) Colord) Enthalpy of Vaporization
5) What happens if you change the number of protons?a) Change the identity of the elementb) Create an isotopec) Create an ion
6) What happens if you change the number of neutrons?a) Change the identity of the elementb) Create an isotopec) Create an ion
7) What happens if you change the number of electrons?a) Change the identity of the elementb) Create an isotopec) Create an ion
8)
symbol 19F1- Cr 2+
Protons 16
Neutrons 16 28
Electrons 16
Charge 2+
9) Express the answer in sig figs:(17.98+12)/3.459
10) Express the answer in sig figs:(17.98*12)-3.459
11) You run a 5.0k race in 32 min, what speed were you going in miles/hour (1600 meters in a mile)
12) Rubidium has two naturally occurring isotopes, 85Rb (relative mass 84.9118 amu) and 87Rb (relative mass 86.9092 amu). If rubidium has an average atomic mass of 85.47 amu, what is the abundance of each isotope (in percent)?
13) fill each square with the CHEMICAL FORMULA (and the charges)
Hypochlorite= Chlorite= Chlorate= Perchlorate=
Hyponitrite= Nitrite= Nitrate= Pernitrate=
Hypocarbonite= Carbonite= Carbonate= Percarbonate=
Hyposulfite= Sulfite= Sulfate= Persulfate=
Hypophosphite= Phosphite= Phosphate= Perphosphate=
14) Name the following or write the chemical formulaNaOH Calcium Acetate Cl2 O3
K2 SO4
CuCN Lead (II) Carbonate Cu(OH)2 Dinitrogen Tetroxide
15) What is the empirical formula for:
C6H12O6 H2O2 MgCl2 Na4Cl4
16) What is the molecular formula for:
Sodium Sulfide Ammonia (Nitrogen Hydride) Magnesium Sulfide Calcium Nitride
17) Write out the chemical formula for the following acids:Hyposulfurous acidPerphosphic acid
18) Write out the name for the following acids:CH3COOH
NH4
19)I combust Ethane and Oxygen
Balanced Equation:
20)I combust Methane and Oxygen
Balanced Equation:
21) If 15 grams of copper (II) chloride react with 25. grams of sodium nitrate to produce sodium chloride and copper (II) nitrate, how much sodium chloride can be formed? Write the balanced chemical reaction.
What is the limiting reactant?
If 11.3 grams of sodium chloride are formed in the reaction, what is the percent yield?
How much excess reactant remains?
22) Mg(OH)2 + 2 HCl → MgCl2 + 2 H2Oa) If 10g Magnesium hydroxide is used, how many moles of HCl is necessary to completely
use up BOTH the Mg(OH)2 AND the HCl?
b) What is the limiting reactant if we have 34 grams Mg(OH)2 and 45 ml of 0.3M HCl?
c) How many grams of MgCl2 are created if the theoretical yield of 38%?
23) Ibuprofen, a headache remedy, contains 75.69% C, 8.80% H, and 15.51% O by mass, and has a molar mass of 412 g/mol. What are the empirical and molecular formulas?
24) what is the equation for density?a) dV=nRTb) c=λdc) d=m/vd) d=mlv
25) 3 groups of students measured the mass of a product from the same chemical reaction. The groups recorded data of 8.83 g, 8.84 g and 8.82 g. The known mass of the product from that reaction is 8.60g. The group values are _____.
a) accurate
b) precise
c) accurate & precise
d) neither accurate nor precise
EXAM 2:4,51) If you have 45 ml of 0.5M NaOH, how many ml of water do I need to add to make the
solution 0.23M?2) If we combine 56 grams of NaCl(s) with 75 ml of 0.4M MgCl2, what is the concentration
of Cl in solution? (Assume the volume of the solid is negligible).
3) Which compound has the highest concentration of Potassium ions?a) 40mL of 5M KClb) 20mL of 3M K2SO4
c) 80mL of 2M KNO3
d) 25mL of 2M K3PO4
4) Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte.
a) LiClO4
b) HClOc) CH3CH2CH2OH (propanol)d) HClO3
e) CuSO4
f) C12H22O11 (sucrose)
5) Write the net ionic equation for each of the following reactions:a. Pb(NO3)2(aq) + KBr(aq) →
b. NaC2H3O2(aq) + HCl(aq) →
c. Acetic acid is neutralized by barium hydroxide
6) Identify the oxidation number for each element. Which is oxidized? Which is reduced?
SO2 + Cr2O72- → SO4
2- + Cr3+
MnO4
- + H2SO4 → Mn2+ + HSO4-
7) Define:Potential Energy= Kinetic Energy= 1 cal= 1kcal=1Cal= Spontaneous reaction= Nonspontaneous reaction= Open System= Closed System= Isolated system= Exothermic= Endothermic=
8) Draw an energy diagram for an exothermic process. For an endothermic process.
9) A system goes from an internal energy of 12.73cal to 15.11cal; what is ΔE? Endothermic or Exothermic?
10) What is the Kinetic Energy in Joules of a 45 mg object moving at 34 cm/sec? In cal?
11) What is the amount of work done on a ball that has a mass of 9.5 g and falls 97 cm?
12) If 34 J of work is done on the system, but 50 J of heat is absorbed from the system, What is the change in internal energy ? Is this an endothermic or exothermic process?
13) Write the heat of formation reaction for NH3.
14) A pound of plain M&M candies contains 96g fat, 320g carbohydrate, and 21g protein. What is the fuel value in kJ in a 42g (about 1.5oz) serving? How many Calories does it provide? 1 lb = 453.6 g ; 17 kJ/g carbs ; 17 kJ/g protein ; 38 kJ/g fat.
EXAM 3:6,7
1) You drop a block of Al into water. The water is 5.000 times as massive as the metal. You know the water has an initial temperature of 25.00 degrees C and after a long time its temperature is 27.00 degree C. The specific heat of Al is .9000 J/gK. What is the initial temperature of the Al?
2) A 10 gram iron sample at 80 degrees C was placed into a 70 ml bath filled with water that was 25 degrees C. The final temperature was 25.85 degrees C. If the specific heat of water is 4.184 J/gK, what is the specific heat of iron?
3) Given the chemical equation
S(s)+O2 (g) → SO2 (g) dH=-297.1 kJ/mol
how much heat is associated with the formation of 7.99g of SO2(g)?
4) Calculate the enthalpy of the following reaction:
CS2(ℓ) + 3O2(g) → CO2(g) + 2SO2(g)
Given:
C(s) + O2(g) → CO2(g)ΔH = ΔH = -393.5 kJ/mol
S(s) + O2(g) → SO2(g) ΔH = -296.8 kJ/mol
C(s) + 2S(s) → CS2(ℓ) ΔH = +87.9 kJ/mol
5) Calculate the change in enthalpy, ΔH, when 1.00 g of hydrogen peroxide decomposes.H2O2(l) → H2O(l) + 1/2 O2(g); ΔH = -98.2 kJ
6) C3H6O (l) + 4 O2 (g) ---> 3 CO2 (g) + 3 H2O (l); ΔH°comb, acetone = -1790 kJUsing this information together with the data below (values in kJ/mol), calculate the enthalpy of formation of acetone (C3H6O).ΔH°f, O2: 0 ΔH°f, CO2: -393.5 ΔH°f, H2O: -285.83
7) Calculate the wavelength light emitted by a photon falling from n=4 to n=1.
8) What is the energy of a photon of electromagnetic radiation with a frequency of 6.75*1012s-
1? (Planck’s constant is 6.626*10-34m2kg/s)
9) How many photons of microwave radiation with wavelength 425 nm are needed to heat 2
cups of water from 20 oC to 100 oC? 1 cup is approximately 250 mL.
10) If 2 moles of photons gives off 920 kJ of energy what is the wavelength of one photon?
11) How many nodes does a 4s orbital have? 3d? Draw them.
12) What is the ground state and nobel gas (condensed) state electron configuration of Ne
O2-
KMg
Mg2+
EXAM 4:8,9
1) Which order is correct when the species are arranged in order of increasing bond
length?
a)NO3-,NO2 - ,NO+ b)NO+ ,NO3
-,NO2 - c)NO2 -,NO3-,NO+ d) NO+ , NO2 -, NO3
-
2) Draw the Lewis structures of the following compounds and classify the following compounds as having ionic, covalent, polar covalent or metallic bonding.
Molecule Lewis Structure Bond Type
BeF2
BCl3
PBr5
SI6
Carbonate ion
SeS3
COH2
Si2F2
OCl-
Ammonium ion
SeO2
3) For each group of elements below, predict the order of increasing electronegativity. a) S, Se, Cl b) Si, Ge, Sn c) B, Ga, O
4) Determine the formal charges of the underlined elements in the following compounds:i) NO2
+
ii) HCNiii) SO3
iv) SO2
5) What is the ground state electron configuration of Co.
6) Write the noble gas electron configuration of an excited Ag atom.
7) From the list below, choose the ions that are isoelectronic with krypton, then arrange them in order of increasing ionic sizeAg+ Br- Cd2+ Sc3+ Se2- Sr2+ Ti2+ Zn2+
8) How many resonance structures does a phosphite ion have?
9) The image below depicts the molecular structure of Corannulene, an aromatic hydrocarbon. How many sigma and pi bonds are present in one molecule of this this compound?
10)
Chemical Formula
IF5 PO3- BH2
- PCl3 XeF2
Lewis structure (with lone pairs
# of electron domains
around central atom
3D structure (ball and stick with accurate bond angles)
Electronic Geometry name
Molecular Geometry Name
Expected Bond Angle(s)
Polar?
Hybridization on central atom?
11) Draw the molecular for F2 and calculate the bond order.
Content since past exam:10, 11
1. If the density of a gas is 0.08987 g/L at STP conditions, what is its molar mass?a) 0.08987 g
b) 2.01 gc) 249 gd) 89.87 ge) 100 g
2. A sample of Ne(g) occupies 4.0 L at 35 OC at 2.0 atm. What is its new volume if the temperature and pressure are changed to 48 OC and 1.0 atm?
a) 0.48 Lb) 2.1 Lc) 6.2 Ld) 7.7 Le) 8.3 L
3. Several commercial drain cleaners contain NaOH(s) and small amount of Al(s). When one of these cleaners is added to water a reaction occurs resulting in the formation of H2 bubbles:
2Al(s) + 2OH-(aq) + 2H2O → 3H2(g) + 2AlO2-(aq)
The purpose of the H2 bubbles is to agitate the solution and thereby increase the cleansing action. According to this equation, how many liters of H2(g) are released when 0.200g of Al are dissolved in an excess of OH- at 25 C and 1.00 atm pressure?
a) 1.00 Lb) 0.111 Lc) 0.0111 Ld) 2.72 Le) 0.272 L
4. Palmitic acid, CH3(CH2)14COOH, is an example of fatty acid found in the human body. The heat of combustion of palmitic acid is -9977 kJ/mol. If the standard heat of formation of H2O(l) at 25 C is -285.8 kJ/mol, (hint, what is the heat of formation equation of water?) what volume of
hydrogen gas is required to react with oxygen gas at 25 C and 1.00 atm to produce an amount of energy equivalent to combusting 100.0 g of palmitic acid?How many molecules of hydrogen are required?
5. A 0.1530 g sample of a gas that reacts with ozone in the atmosphere exerts a pressure of 470.g torr in a 50.00 mL vessel at 298.0 K. What is the molecular formula of the gas given its elemental composition: 9.934% C; 58.64% Cl; and 31.43% F.
6. If you have gas with a pressure of 3.4 atm that is composed of 14 grams of Cl2 and 6 grams of Neon, what is the partial pressure of on Chlorine and on Neon?
7. If you have a gas that is 46 percent by mass O2, 13 percent by mass Argon, and 41 percent by mass F2, and the partial pressure of Argon is 0.32 atm, what are the partial pressures on the other two elements?
8. What is the rate of effusion for a gas that has a molar mass thrice that of a gas that effuses at a rate of 4.2 mol/min?
9. Calculate the rate of flow of O2(g) through the walls of a porous tube if H2(g) flows at the rate of 3.95x10-3 mL/s under identical conditions.
10. How much work is done by a gas that expands from 2 to 5 liters against an external pressure of 750 mmHg?
11. Which substance has the highest normal boiling point?a) CH3Cl
b) CH3Br
c) CH3I
d) CH4
e) CH3OH
12. In liquid SO2, which of the following intermolecular forces operate in the liquid phase: (1) ion-ion; (2) ion-dipole; (3) dipole-dipole; (4) dispersion?
a) (1) and (2)b) (3) and (4)c) (1) and (3)d) (2) and (4)e) all of them
13. Which of the following has lowest boiling point?a) HFb) HClc) HBrd) HI
14. Which of the following has the highest vapor pressure?a) Ethane, CH3CH3
b) Dimenthyl ether, CH3OCH3
c) Ethyl alcohol, CH3CH2OH
15. Molecules are more likely to evaporate if they have:(High/Low) Temperature(High/Low) Kinetic Energy(High/Low) Intermolecular Forces(High/Low) Vapor Pressure(High/Low) Molecular Weight(High/Low) Surface Tension
16. Calculate the amount of heat needed to convert 96 g of ice at –50 ºC to steam at 110 ºC. c(ice) = 2.06 J/g°C, c(H2O) = 4.184 J/g°C, c(steam) = 1.87 J/g°C, DH(fus) for H2O is 334.J/g, DH(vap) for H2O is 2260 J/g
17. On the phase diagram, the substance exists in which phase on line A?a) gas and solidb) gasc) liquidd) liquid and solide) liquid and gas
18. On the phase diagram, the substance exists in which phase on line B?a) gas and solidb) gasc) liquidd) liquid and solide) liquid and gas
19. On the phase diagram, the substance exists in which phase on line C?a) gas and solidb) gasc) liquidd) liquid and solide) liquid and gas
20. On the phase diagram, the substance exists in which phase at point D?a) gas and solidb) gasc) liquidd) liquid and solide) liquid and gasf) liquid, gas, and solid
21. What is the critical temperature and pressure?a) 216.6 K and 5.2 atmb) 197.5 K and 1 atmc) 304.25 K and 73 atm
22. At what pressure is the normal boiling point of a substance?a) 760 atmb) 1 torrc) 1 mm Hgd) 1 atm
23. Rank the four intermolecular forces in order of increasing strength.