HW1-5 - 1-2 Fundamental Concepts Chap. 1 4. In a medical...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1-2 Fundamental Concepts Chap. 1 4. In a medical test for a certain molecule, the concentration in the blood is reported as 123 mcg/dL. What is the concentration in proper 81 notation? Solution: 123 mcg/dL = 10-3io-2 g/10-1 L = 1.23 X 10-6 g/L = 1.23 p,g/L. 5. How many neutrons and protons are there in each of the following nuclides: (a) loB, (b) 24Na,(c) 5900, (d) 208Pb,and (e) 235U? Solution: Nuclide neutrons protons lOB 5 13 5 11 24Na 59CO 32 126 143 27 82 92 208Pb 235U 6. What are the molecular weights of (a) H2 gas, (b) H2O, and (c) HDO? Solution: From Table A.3, A(O) = 15.9994gfmol; from Table B.1 A(H) = 1.007825 gfmol and A(D) = 2.014102gfmol. (a) A(H2) = 2 A(H) = 2 x 1.007825= 2.01565 g/mol (b) A(H2O) = 2 A(H) + A(O) = 2 x 1.007825 15.9994= 18.0151 g/mol + (c) A(HDO) = A(H) + A(D) + A(O) = 1.007825 2.014102+ 15.9994 + = 19.0213 g/mol What is the mass in kg of a moleculeof uranyl sulfate UO2S04? Solution: From Table A.3, A(U) = 238.0289 /mol, A(O) = 15.9994g/mol, and A(S) = g 32.066 g/mol. The molecular weight of UO2SO4is thus A(UO2S04) = A(U) + 6A(O) + A(S) = 238.0289+ 6(15.994)+ 32.066 = 366.091 g/mol = 0.336091kg/mol. Since one mol contains Na = 6.022 X 1023molecules,the mass of one molecule of UO2S04 = A(UO2S04)/Na = 0.366091/6.002 x 1023 = 6.079 X 10-25 kg/molecule. July 24, 2002 7. ...
View Full Document

This note was uploaded on 02/01/2010 for the course ECE 4130 taught by Professor Cady during the Spring '06 term at Cornell University (Engineering School).

Ask a homework question - tutors are online