ps1 - Chem 120B Problem Set 1 Due February 1 2008 1(i...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Chem 120B Problem Set 1 Due: February 1, 2008 1. (i) Problem 16-6 in McQuarrie & Simon’s Physical Chemistry textbook. (ii) Let N be the number of molecules contained in the ultra-high vacuum chamber of Problem 16-6. How large are typical fluctuations in N ? Using results from lecture, calculate both their absolute size, radicalbig ( ( δN ) 2 ) , as well as their size relative to the mean, radicalbig ( ( δN ) 2 ) / ( N ) . (iii) Assume that the distribution of N is Gaussian, P ( N ) e ( N −( N ) ) 2 / 2 ( ( δN ) 2 ) . Estimate the likelihood of a 10% fluctuation in density by computing p (0 . 9 ( N ) ) /p ( ( N ) ) for the apparatus described in Problem 16-6. Would such a relative fluctuation be more or less likely at higher pressures? 2. (i) Show that the mean square fluctuation in any quantity A can be written in terms of its mean and mean square values, ( ( δA ) 2 ) = ( A 2 ) − ( A ) 2 . (Here, as usual, the fluctuation in A is defined as δA = A − ( A ) .) (ii) Generalize this result to the case of two different fluctuation quantities, i.e., show that ( δA δB ) = ( AB ) − ( A )( B ) .
Image of page 1

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern