DOC PREVIEW
UL Lafayette CHEM 107 - Final Exam

This preview shows page 1-2-3 out of 9 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 9 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 9 pages.
Access to all documents
Download any document
Ad free experience
View full document
Premium Document
Do you want full access? Go Premium and unlock all 9 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 9 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

LAST NAME, FirstCHEM 107 (Fall-2006)Final Exam (100 + 4 pts)Name: ------------------------------------------------------------------------, Clid # ------------------------------ LAST NAME, First(Circle the alphabet segment of your LAST NAME): A, B C-G H-N O-S T-Z Please answer the following questions:Part I: Multiple Choices (44 pts: 22 @ 2 pts each + 4 pts bonus). Circle the ONE best answer:1. Which of the following species have bent (angular) molecular shape?I) CO2II) OF2III) NO2+IV) NO2-a) only II b) only IV c) II and IV d) I and III2. Which of the following ions is expected to be paramagnetic? a) Zn2+ b) S2-c) Cu+d) Ti3+3. The ground state electron configuration of tantalum, Ta (Z = 73) isa) [Xe] 5d3 6s2b) [Xe] 4f14 5d3 6s2c) [Xe] 4f14 6d3 6s2d) [Xe] 4f14 5d54. The oxidation numbers of phosphorus, P in PCl3 and P2O74- are:a) -3 and +10, respectively b) -3 and +7, respectively c) -3 and +5, respectively d) +3 and +5, respectively 5. If a gold ring has a mass of 5.50 g in temperature from 25.0 to 28.0 ºC, how much heat is absorbed? (specific heat of gold is 0.129 J/g ºC)a) 2.1 J b) -2.1 J c) 0.24 J d) 130 J6 Which of the following statements is false?a) An electron transition from n = 1 to n = 3 absorbs energy.b) Light emitted by an n = 5 to n = 2 transition will have a shorter wavelength than that fromn = 4 to n = 2 transition.c) An atom of group 16 has two unpaired electrons.d) All of the above. 7. Which of the following molecules is expected to be polar?a) BeF2b) SF6c) XeF4d) OF218. Calculate ∆H° for the following reaction using the given enthalpies of formation.2 NO (g) + 5 O2 (g) 2 NO2 (g)∆Hf° NO (g) = 90.25 kJ/mol & ∆Hf° NO2 (g) = 33.18 kJ/molb) +57.07 kJ b) -57.02 kJc) -114.14 d) +114.14 kJ9. Which of the following is most likely to involve sp3d hybrid orbitals at the central atoms?I) ClF3II) BrF5III) XeF4IV) SF4a) I and IV b) only II c) only IV d) II and III10. Which of the following has the greatest ionization energy?a) Br b) Sn c) Se d) Cl11. Which name is incorrect?a) Ca3P2: calcium phosphide b) Na2S: sodium sulfide c) P2S5: diphosphorus pentasulfide d) Co2O3: cobalt(III) trioxide 12. Aluminum and oxygen react according to the following equation:4 Al (s) + 3 O2 (g) 2 Al2O3 (s) What mass of Al2O3 (102.0 g/mol), in grams, can be made by reacting 2.3 g of Al with excessoxygen?a) 8.7 g b) 17.4 gc) 4.3 g d) no answer was give13. If 400.0 mL of 0.375 M NaOH is added to 280.0 mL of 0.600 M HNO3, will the mixture be a) neutral b) basic c) acidic d) amphoteric14. Calcium metal and bromine react to form calcium bromide, CaBr2. Which statement is correct?a) Ca atom loses two electrons and becomes Ar atom.b) Br atom gains an electron and become Kr atom.c) The Ca and Br atoms change into different, more stable atoms.d) CaBr2 is predominantly an ionic compound.15. The standard enthalpy change for the following reaction is -53.0 kJ. 2 HI (g) H2 (g) + I2 (s)What is the standard enthalpy of formation of HI (g)?a) 53.0 kJ b) -105.9 kJ2c) 26.5 kJ d) -53.0 kJ 16. An atom containing 26 protons and a mass number of 59, would be:a) Fe b) Coc) As d) Ni17. The element X occurs naturally to the extent of 20.0% 12X and 80.0% 13X. the atomic mass of X is nearesta) 12.8 b) 12.2 c) 12.5 d) 13.018. Equal volumes of an unknown gas and nitrogen (N2) gas takes 5.37 min and 3.55 minutes, respectively to effuse through a small hole. Calculate the molar mass of the gas. a) 64.1 b) 12.2c) 42.4 d) 128 19. The greatest deviation from the Ideal Gas Law is expected at:a) high T, high P b) low T, high Pc) high T, low P d) low T, low P20. A 4.8 g sample of a compound of nitrogen and oxygen contains 3.02 g of oxygen. What is the simplest formula?a) NO2b) N2O3c) N2O d) NO21. Which of the following ions has the largest ionic radius?a) Se2-b) Cs+ c) S2-d) Sr2+ 22. In the phase diagram shown here. Which statement applies? Phase Diagram of Substance Z a) The path A C represents sublimation.b) Following the path A B C, the compound would first liquefy and then vaporize.c) If the compound is in state A, continued reduction of the pressure (at constant T) will cause it to melt.d) None of these statements is correct. 23. Consider the above phase diagram, what is the normal melting point of the pure substance Z?a) +18 ºC b) -22 ºC 3c) - 2 ºC d) +4 ºC 24. Using the same diagram, if the average atmospheric pressure at the top of certain mount, which isabout 19,000 feet above the sea level is 0.526 atm, What is the approximate boiling temperatureof the liquid? a) 20 ºC b) 140 ºCc) 5 ºC d) can not be determined from this graph Part II. Bonding and Chemical Equations (26 pts):A) Bonding & molecular structure (12 pts):1. Draw the Lewis structure for the SO2 molecule, draw the resonance structures, if there is any then predict: a) the molecular shape b) hybridization of the central atom c) number σ and π bonds d) bond angleB) Chemical Equations (16 pts):2. (8 pts) Balance the following redox equation in acidic solution:UO22+ (aq) + Te (s) U4+ (aq) + TeO42- (aq),Then identify the oxidizing agent and how many electron(s) are transferred per one mole of the oxidizing agent.4Balanced equation:Oxidizing agent: --------------Number of electrons/mole of oxidizing agent: -------- Lewis Structure & resonance structures (if any)a) Molecular shape: ------------------------b) Hybridization of the central atom: -------c) # of σ bonds ------- and # of π bonds --------d) Bond angle: -----------------2. (6 pts) Write the balanced chemical equation and the net ionic equation for the reaction between aqueous solutions of HNO3 (aq) and CaCO3 (s) and then identify the spectator ion(s)Part III. Calculations (30 pts: 5 @ 6 pts each) Show all work for full credit. Please express all answers with the proper units and correct number of significant figures.1. Given the following equations:2 H2 (g) + O2 (g) 2 H2O (l) ∆Hrxn° = -571.6 kJ N2 (g) + O2 (g) 2 NO (g) ∆Hrxn° = +180.5 kJ N2 (g) + 3 H2 (g) 2 NH3 (g) ∆Hrxn° = -92.2 kJ


View Full Document

UL Lafayette CHEM 107 - Final Exam

Download Final Exam
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Final Exam and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Final Exam 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?