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MARITIME COLLEGE STATE UNIVERSITY OF NEW YORK CHEMISTRY 212 FALL 2024 FINAL EXAM PRACTICE NAME_ OMA ss 84 PROFESSOR ID# PART 1 The following 19 questions are multiple choice. Each is worth 3 points. The best 18 questions count towards your exam score; the remaining 1 question and 2 points from a question in Part II count as 5 points of extra credit if all are correctly answered. 1. The covalent bond: (i) is non-directional Gi) occurs in compounds such as CaCl and MgO % (iii) is characterized by sharing of the valence electrons (a) @ only b) (ii) only o) (iii) only (@) @ and (ii) (e) (i and (iii) 2. ABCC unit cell has _Catoms per cell and a FCC unit cell has yy atoms per cell. (a) 4,2 (b) 5,14 ce) 9,14 (a) 2,4 e) 14,9 3. Which does not match the name correctly with the defect? Je Dede ea ~.) | 16 OO )@, Salat he (c) interstitialcy (d) Schottky imperfection 4. What are the Miller indices for the plane shown? 4 sy (a) (643) . (b) (132) () (623) (@) (264) © (23 4) 5. Inthe crystal structure of the ceramic ZnS, there are i 4 a ; @ a wvesén: Foc postions zs i L)- @: 3(&)*z)=4 ) ‘ (e) 18 Heyig |:lreo 6. When comparing 2 samples of the same metal, the one with larger grains will be EeFstrong and pry ductile. (a) more, more (b) less, less (c) more, less Si less, more 7. Which of the following conditions favor the creation of a substitutional solid solution for two elements? <5 )yy11|Q7 (i) dissistiilar atomic radii Gi) same-déhsity (iii) same crystal structure (a) @ (b) (ii) (iii) (ii) and (iii) (&) @ and (ii) 8. Which is not correct? (a) The greater the modulus of elasticity, the stiffer the sample. (b) The Tensile Strength is the maximum strength on a stress strain diagram; maintaining that stress will fracture the sample. (c) The Yield Strength is the point where the transition from elastic to plastic deformation is considered to occur. dena: |e @ necking begins to occur at the Yiekf Strength 13. (b) (©) (d) (2) 14. (a) (b) (d) (2) 15. @ 8 (©) (d) © 16. a) (b) © @) 17. The Wes reaction which occurs at point(s) __is eutectoid. point A F-OLN pointB L+vAt © COIECHIC pointC Y bea & POriteOHiCc. points A, B and C are all peritectic reactions none of the points (A, B, C) are peritectic reactions A sample which has 80 % B and is at room temperature can be described as hypereutectoid with proeutectoid 8 hypereutectoid with proeutectoid 7 hypoeutectoid with proeutectoid 0 hypoeutectoid with proeutectoid y hypoeutectoid with no proetectoid phase How many grams of carbon are in 100 g of 1380 steel? & 08g SY ; ta 5 O.DOLC (BB Yi00a"4 80g 0.13 g 13g Which is true for a thermosetting plastic. ae it is recyclable Yrermd pi ashics it becomes less rigid on heatin; it cross-links when it is heated it appears as a tangled mass of molecules The data in the table are the molecular weight distribution for a sample of polyvinyl chloride. One mer of PVC has the formula CH2CHCI. What is the average molecular weight of the sample? (a) 62.5 g/mol a ey OE (@) 21150 g/mol tooooseane | teen ease EDO (c) 22500 g/mol 18,000-20,000 | 17,500 x O22 650 20,000-25,000 | (22,500 0.27 25,000-30,500 | 27, 2 OO (d) 338 g/mol ae ee (e) 360 g/mol 36,000-49,000 | 47,800 ave 1SCo . . FOO 18. Ifa piece of lead were placed in a solution of it would oxidize. —_— a) NP ZN DOVne Cc 2+ (oy Ove ne Pe o Al Plow __ = Pig" * —~ - (@) Pb* : j Po Yer Xo: (e) none of the above recrd to Ai e eee a nrore- hoes a PEAUEHT1ON WIth 4 19. Is sodium oxide a protective oxide coating? Density of Na2O = 2.27 g/cm? (a) yes because 1 < PB ratio <2 Vs M ad (b) yes because PB ratio < 1 am (c) yes because 2 < PB ratio <1 1. , . @ no because PB ratio <1 = (@2U9 +n?) = 2 oS (e) no because 2 < PB ratio ¢ ay 2=2. CF) 20. Ina Fe/Ni galvanic cell, nickel is | CC. and is the C atiude, (a) oxidized, cathode iw) Qi Zea NM, =) ED © reduced, cathode nada i =40 oxidized, anode re“sZy Ste (d) reduced, anode >jez fet +2e * 440 21. Aluminum is being refined by electroplating. Ifthe current is 2 x 10° A, what mass of aluminum is plated in 1 hour? 8 moe STAM = (2 n1OCA)(56008)(2 HONS 187 kg ey =z DOC’ @) S4ke (D(GG00C) 22. Which of the following statements correctly explains why the mentioned steel does not oxidize? (a) Galvanized steel is protected by a zinc-oyid€ layer. (b) Stainless steel is protected by a coating of chromium. (c) Galvanized steel is protected by a’chromium-oxide layer. Galvanized steel is protected by a coating of zinc. \ ~~ Stainless steel is protected by a \ zint-oxide layer. GQAaWANiZEA Steak layer 68 En UtuchN |! MOre ANOUC han Fe. TIOINIESS Steel - MOhbcr Gitaw Chin rom iinMn ~OXx ide lover frOreckss tt 4. What is the attractive force (in Newtons) between a pair of oppositely charged ions when they are at equilibrium, in Fe2O3? q Fes O6t Fe -GOCOUGx/0 mos ror: Bz }Sz — iS > *O%C — (I GANO T9Inm 4G xIC ° 5. Draw the plane or vector in the unit cube. t a Giz -l-l le B [oTzZ] “te -i_ 7 O 6. Acsingle crystal of a metal that has the BCC crystal structure is oriented such that a tensile stress is applied in the [100] direction. The magnitude of this stress is 4.0 MPa. and the resolved shear stress of interest is in the [1 1 1] direction on the (1 0 1) plane. 5 A. Draw and label the three relevant directions and one plane in the unit cell. Vv oe ae //\ | oblerLert a aN Ms [rot “E> plane=(10T) B. What is the critical resolved sheer stress in MPa? RESIN att _ 2 FP > It The stress strain curve corresponds to a sample originally 10 cm long and with a2 cm x 2 cm cross section. What is the yield strength (MPa)? sunenes waneanes nae eee a OOM Fa “ What is the tensile strength (MPa)? ZOCOM Pa What is the Elastic Modulus (MPa)? é =o . (00 = & 2 Re -l2x)0°M Fa A steel bar has the following properties: ed 3500 N Elastic Modulus = 190 GPa oz TT { 2410 ) Yield Strength = 580 MPa Tensile Strength = 850 MPa x) xO cone A. Calculate the stress in MPa. B. Cc. has the dimensions shown and is subjected to it BY ‘orce shown. 14 Hy a | 2500 mm OrBZOOn = Hq OIF wee EOEKOMe \HGomPa Is the bar in the elastic leon? Ves OSYD What is the final length of the bar (in mm) while under 3500 N? Ess COE pe- 2500 » OOZG= 2500 G Haoaichhe . 00% "| Fez 2506-Smm) 1a0x*10% Pa D. What is the maximum tensile load permitted (in Newtons) without causing plastic deformation? aw) ra a —_—_ ~ 5g0%10% P= F,0F IO AM [Fz 4100-6] « 10. Below is an isothermal transformation diagram for eutectoid steel. One thin piece of eutectoid steel at 750°C is subjected to the 3-step heat treatment listed below. Fill in the table by putting the percent (0, 25, 50 or 100) of each microstructure or phase and giving the percent of the sample that is composed of the a + FesC phases, after each step. A. Quenched to 500°C and held there for 5 seconds B. Quenched to 300°C, held at 300°C for 500 seconds C. Quenched to room temperature and then reheated at 350°C for 1 day ¢ ; - 800 1 — 700 ===} Coarse pearlite 600 al 500! Fine pottine ] 1 SSS Bainite 300 A { woes Ne 200 [= 100 Adec | 1 mir Lhour day F) GT FTC TT POP FP PF O1 1 0 1 1° 10* 105 Time, seconds Y Bainite Martensite | Tempered Pearlite a+FesC Martensite DO DO QO | 29 | 29 QO baw 29 29) 50 | 100 10 11. A mer of polymethyl methacrylate is shown below. The average molar mass of a chain of polymethy! methacrylate is 25,440 g/mol. y" A. What is the molar mass of a mer of polymethyl methacrylate? ar 5i2g)* 210g) + BC14)-||00Amoes) a H \ B. What is the average number of mers in a chain of polymethyl OCH3 methacrylate? - 254CO -[254.5) DP “TOO C. Asample of polymethyl methacrylate has a mass of 1 g. How many chains does it contain? 1a PM) imce Om |G O%xIO7BhOINS 125.4404] jmve Cram [2.57 xO Cheins) 12A.Label Galvanic cell diagram for a cell consisting of a silver electrode in contact with 1.0x10? M AgNOs and a chromium electrode in contact with 2.0x10? M Cr(NO3)3 ¢ Cathode and anode with the metal/ion cach is % Ke e Direction of electron flow e Direction of flow of Ag* and Cr** ions on/off the bars B. What is the reading on the voltmeter? Ags ox ARs F949 5 Cretese Cr FA . a B=. 495% + OOF [a(ix109= Ch] || Ex) Es. TH © OBS Ion (ex io) HE Meh) E ceee=.66OG L,FFTS | [4 Seven Anode C. What is the balanced reaction represented in this Galvanic cell? y fd Agree wA a) Cre t+ Dk Cr 7 G Creer re [= Rat*Crs SAq +eret |