Name Final Exam- Page 1 CO 3. Na 2 MOSTLY ABOUT COPPER CHEMISTRY. 1. (12 points) Copper is a (metal)(metalloid)(nonmetal) with a symbol of

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1 Name Final Exam- Page 1 1. (5 points) Names and Formulas of ommon ompounds and Ions Ammonium nitrate Aluminum hydroxide opper(i) oxide Sulfur trioxide Na 2 3 MSTLY ABUT PPER EMISTRY 1. (12 points) opper is a (metal)(metalloid)(nonmetal) with a symbol of and an atomic number of. It is in Group and period of the periodic table. The element has protons in the nucleus. A copper(ii) ion has e l e c t rons outside of the nucleus. The electron configuration for a copper atom is (use the spectroscopic notation and the noble gas notat i o n ) The electron configuration for the copper(ii) ion (u 2 + ) is If copper-63 is the most abundant isotope of the element, an atom of this isotope has n e u t rons in the nucleus.

2 Name Final Exam Page 2 2. (11 points) When copper reacts with iodine, it forms ui. a ) Balance the following equation u(s) + I 2 ( s ) ui(s) b ) If you used 2.36 g of copper, how many moles is this? i ) 26.9 mol i i ) 2.36 mol i i i ) mol i v ) mol c ) opper metal has a density of 8.96 g/cm 3. If you use 50.0 g of copper, this amounts to cm 3 of the metal. d ) If you use 0.20 mol of copper, what mass of iodine, I 2, is re q u i red to completely consume the metal and form ui? i ) g i i ) 50.8 g i i i ) g i v ) g 3. (4 points) Identify each of the following reactions as an a c i d - b a s e reaction, a p recipitation reaction, a g a s - f o rm i n g reaction, or a redox re a c t i o n. ul 2 + Na 2 3 u Nal u + 2 AgN 3 u(n 3 ) Ag u() S 4 us u l ul

3 Name Final Exam Page 3 4. (6 points) The reaction you recently did in the lab was u S 4 (aq) + 4 N 3 (aq) u ( N 3 ) 4 S 4 If you used 10.0 g of us 4 (molar mass = g/mol), what volume of 3.0 M N 3 (aq) is re q u i red to completely consume the us 4? a ) 10.0 ml b ) 20.0 ml c ) 83.6 ml d ) 750. ml If you isolated 12.6 g of u(n 3 ) 4 S 4, but the theoretical yield was 15.0 g, what was the perc e n t- age yield of u(n 3 ) 4 S 4? a ) 12.6 % b ) 15.0 % c ) % d ) % 5. (3 points) In the industrial production of copper metal, copper(i) oxide (143.1 g/mol) reacts with c o p p e r ( I I ) sulfide (159.1 g/mol). 2 u 2 ( s ) + u 2 S 6 u(s) + S 2 ( g ) If you combine g of u 2 and g of u 2 S, what is the theoretical yield of u? a ) 500. g b ) 665 g c ) 1000 g d ) 1197 g e ) 1330 g f ) Not a one of these answers is corre c t! 6. (3 points) Describe each compound below as s o l u b l e or i n s o l u b l e in water. a ) u 3 c ) u B r 2 d ) u 3 ( P 4 ) 2

4 Name Final Exam Page 4 6. (3 points) A compound with the empirical form u l a K u l 3 has been isolated. Its molar mass is 418 g/mol. What is the molecular form u l a of the compound? a ) K u l 3 b ) K 2 u 2 l 6 c ) K 3 u 3 l 9 d ) None of the above. 7. (3 points) Bubbling through a solution of ul in concentrated l, gives the compound u ( ) l. ul + u ( ) l The reaction can be used to estimate the content of gases. Let us say you want to determine the content of the exhaust gas from your car. You use 100 L of exhaust gas and isolate from it g of u()l (molar mass = 127 g/mol). ow many grams of did the 100 L of exhaust gas c o n t a i n? a ) 2.46 g b ) 9.63 g c ) 100. g d ) None of the above. My car does not emit! 8. (6 points) opper ion forms complexes with many organic and inorganic molecules and ions. ne is with biuret, and the result is a beautiful violet material. 1 N N 3 N a ) What are the angles indicated on the molecule s stru c- t u re? 2 Biuret 1 = 2 = 3 = b ) ow many bonds are there in the molecule? c ) What is the weight percent of N in the molecule? i ) 13.6 % i i ) 23.3 % i i i ) 40.8 % i v ) 73.6 %

5 Name Final Exam Page 5 9. (2 points) You wish to pre p a re copper(ii) phosphate. Use some combination of the compounds below to make this compound. u 3 l u ( N 3 ) 2 3 P 4 u S 4 N a 3 P 4 Describe your approach by writing a c o m p l e t e, balanced equation. 10. (3 points) You need 100. ml of 0.15 M us 4. You are given 1.00 L of 0.60 M us 4 and the necessary glassware. Describe how you would prepare the desired solution (6 points) You have synthesized a compound with the formula Li n u n + 1. To find the value of n, you react the compound with acid. For example, if n = 1, then the reaction is L i u l Lil + ul 2 + 5/2 2 If you analyze the solution for copper ion, and know that n = 1 or 2, you can find the form u l a for the compound. If g of Li n u n + 1 ( w h e re n = 1 or 2) gives 10.0 ml of a solution with a u 2 + concentration of M, does n = 1 or 2? Please show your work!

6 Name Final Exam Page (5 points) opper metal reacts with nitric acid. u ( s ) + 2 N - 3 (aq) (aq) u 2 + (aq) + 2 N 2 (g) ( l ) Assign oxidation numbers to u ( s ) N in N - 3 N in N 2 The substance that has been oxidized in the reaction is and the oxidizing agent i s TERMEMISTRY 1. (3 points) Suppose 81.0 J of heat energy is transferred into a copper bar with a mass of g. The temperature of the bar increases from 20.0 to What is the specific heat capacity of the copper? a ) J/g K b ) J/g K c ) J/g K d ) J/g K e ) None of the above 2. (2 points) Which re q u i res more heat to warm from 22 to 85, 50.0 g of water or g of ethylene glycol. (Specific heat of glycol = 2.39 J/g K and of water = J/g K) _ 3. (2 points) Methane ( 4 ) and propane ( 3 8 ) are used as fuels. 4 (g) (g) 2 (g) (l) 3 8 (g) (g) 3 2 (g) (l) = kj = kj Which fuel provides more heat energy per gram, methane or propane? 4. (3 points) Use the table of standard enthalpies of formation in your textbook to calculate the enthalpy change for the combustion of 1.00 mol of butane, a ) rx n = kj b ) rx n = -888 kj c ) rx n = kj d ) rx n = kj e ) Not a one of them! (g) + 13/2 2 (g) 4 2 (g) (l)

7 Name Final Exam Page 7 5. (3 points) Using the enthalpy data below, and ess s Law, calculate the standard molar enthalpy change for the formation of magnesium carbonate from Mg, 2, and 2. M g ( s ) + 2 ( g ) + 1/2 2 (g) M g 3 (s) r x n =? M g ( s ) + 1/2 2 (g) M g ( s ) M g ( s ) + 2 ( g ) + 1/2 2 (g) M g 3 ( s ) ( a ) rx n = kj/mol ( b ) rx n = kj/mol ( c ) rx n = kj/mol ( d ) rx n = kj/mol ( e ) I don t think it is any of these. But then who knows! = kj = kj ATMS, ELETRN NFIGURATINS, PERIDI PRPERTIES 1. (3 points) Spectra and Radiation a ) Which color of light in the visible spectrum has the shortest wavelength? b ) Which color of light in the visible spectrum has the lowest energy? c ) Is the energy of red light higher or lower than that of x-rays in the dentist s office? 2. (4 points) Using the s p e c t roscopic notation [e.g., 1s 2 2 s 2 ], write electron configurations for each of the following: S (do not use the noble gas notation for this case) U r a n i u m 3. (4 points) Using the orbital box notation, write electron configurations for the following atoms or ions. Please use the noble gas notation for both of these! l V 2 +

8 Name Final Exam Page 8 4. (6 points) E l e c t ron onfigurations a ) What element has the electron configuration [Ar] 3d 8 4 s 2? b ) What element has a 2+ ion with the configuration [Ar] 3d 7? c ) ow many unpaired electrons are there in a Mn 2 + ion? d ) Is a merc u ry(ii) ion, g 2 +, paramagnetic or diamagnetic? e ) What 2+ ions in the first series of transition elements (Sc through Zn) have two unpaired elect rons? f ) With what element is the n = 4 shell of electrons completed? 5. (9 points) Atomic Stru c t u re a ) ow many orbitals are there in a subshell labeled d? b ) ow many orbitals are there in the n = 4 shell? c ) For a 3d orbital, the value of n is and the value of l is. d ) Indicate what type of orbital is illustrated below. letter e ) ow many e l e c t ro n s can be associated with each of the following sets of quantum numbers? Quantum Number Set n = 4 and l = 1 n = 3, l = 2, m l = -1 Number of Electrons

9 Name Final Exam Page 9 6. (12 points) Periodic Tre n d s a ) b ) c ) d ) e ) f ) f the elements, S, and F, which has the largest atomic radius? Which is larg e r, l or l -? What element in the alkali metal group has the largest radius? What element in the second period has the largest (most positive) electron affinity? What element in Group 3A has the largest ionization energy? Place the following elements in order of increasing ionization energy: B, Al, lowest IE highest IE g ) Which ion is larg e r, a 2 + or l -? h ) Which of the following ions is (are) unlikely to exist: Ti 5 +, F 3 -, Al 3 +, Sr 2 +, Pt 4 +? _ i ) f the elements Na,, F, l, which has the largest atomic radius and which has the largest ionization energy? 1. (4 points) Geometry of molecules. STRUTURE AND BNDING Angle 1 = Angle 2 = Angle 3 = a ) Indicate the bond angles in the dihydroxyacetone molecule pictured below. b ) I R L E the s h o rt e s t carbon-oxygen bond (or bonds) in the molecule.

10 Name Final Exam Page (17 points) opper reacts with N 3 - to produce N 2 - and N 2. a ) Number of valence electrons in N 3 - =. Draw an electron dot stru c t u re for N 3 -. The e l e c t ron pair geometry of N 3 - is The shape or molecular geom - e t ry of the N 3 - ion is and the N angle is. b ) Number of valence electrons in N 2 - = Draw an electron dot stru c t u re for N 2 - and a l l possible resonance stru c t u re s. The e l e c t ron pair geometry of N - 2 is The shape or molecular geom - e t ry of the N - 2 ion is and the N angle is. c ) Draw an electron dot stru c t u re for the N 2 molecule. (The arrangement of atoms is N N.) Is N 2 a polar or nonpolar molecule? _ What is the f o rmal charg e on the central or middle N atom?

11 Name Final Exam Page (5 points) Polarity of Bonds and Molecules Indicate which bond is more polar: a ) or B b ) or Indicate whether each molecule below is or is not polar. l l l l l A oliday Gift (1 points) 1. Who will win the Superbowl next January? 2. What is your favorite holiday re c i p e? Give us the recipe for our collection.