Question

To five significant figures, what accelerating potential difference AV is required to detect the ion 0 ? The masses of the atoms are shown in the table; the mass of the missing electron is less than 0.001 u and is not relevant at this level of precision. Use the following constants: 1 u = 1.6605 x 10-27 kg, e = 1.6022 x 10-19 C. (Figure 1) shows a mass spectrometer, an analytical instrument used to identify the various molecules in a sample by measuring their charge-to-mass ratio q/m. The sample is ionized, the positive ions are accelerated (starting from rest) through a potential difference AV, and they then enter a region of uniform magnetic field. The field bends the ions into circular trajectories, but after just half a circle they either strike the wall or pass through a small opening to a detector. As the accelerating voltage is slowly increased, different ions reach the detector and are measured. Consider a mass spectrometer with a 200.00 mT magnetic field and an 8.0000 cm spacing between the entrance and exit holes. Atomic masses 12c 12.000 u 14.003 u 14N 160 15.992 u Express your answer to five significant figures and include the appropriate units. AVO: = Value Units Submit Request Answer Part B What accelerating potential difference AV is required to detect N? Express your answer to five significant figures and include the appropriate units. AVN = Value Units Figure < 1 of 1 Submit Request Answer Part C + AV - Although N and Cot both have a nominal molecular mass of 28, they are easily distinguished by virtue of their slightly different accelerating voltages. What accelerating potential difference AV is required to detect Cot? Express your answer to five significant figures and include the appropriate units. MH* O O ? Alco+ = Value Units Detector Submit Request Answer

Answer 1

Part ) d 8.0000 Cm -» A 200 00 MT adu urulor path reud, u tho peed ion in the magvotie ald thon loiu have tho Urcle aceod Yodius mu2 2 m Thw the oterchal derene rqwred 2m AV Thn 2x15:992x 1-6 605 X10 X A V=96.537 VO IK faxt (A) for N 4,B,d ame Sinle AVN 96.534 Volts =l0.25 V6l 2x15.492 X 2x14.bo3 AVNt1D.25 vo It Part C) mco(12000+15-8 )u 27.992 4 POAVot AVN AVyt2xu003 27 99 2 :X 110.25 V Avcotb.0 Vo H