{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# chem_126_common_1_2009_0s0sANSWER1S_sz0zz - Feb 20 2009...

This preview shows pages 1–3. Sign up to view the full content.

Feb. 20, 2009 Chemistry 126 Common 1 Questions 4-6 1 1.5 2 2.5 3 3.5 0 10 20 30 40 50 60 70 80 Time (min) [R] -1 (M -1 ) [A] has no effect on the rate. From runs 2 and 3, doubling [B] doubles the rate. So the reaction is first order with respect to [B] and the overall reaction order is 0+1 = 1. 1) The overall reaction is 2A(g) + C(s) 2D(g). What is the reaction rate? A. k [A] 2 [C] B. k [A][C] C. k [A] 2 D. k [A] E. Unknown—it must be determined from experimental data 2-3) The table gives the experimental data for the reaction: A(g) + 2B(g) C(g) + D(g) at 500 K. 2) What is the order of the reaction with respect to A? From runs 1 and 2, changing A has no effect on the rate. 3) What is the overall order of the reaction? (You first need to find the order with respect to B.) 4) 1/reactant concentration is plotted versus time and produces a straight line. What is the order of the reaction? [ ] [ ] nd 1 1 For 2 order: yields a straight line. o kt R R = + 5) What is the rate constant (include units)? A. 38 M/min B. 38 M -1 min -1 C. 38 M -1 min D. 0.026 M/min E. 0.026 M -1 min -1 6) What is the approximate half-life for a starting concentration of 0.67 M? Run [A] (M) [B] (M) Rate (1/hr) 1 0.25 0.15 0.33 2 0.40 0.15 0.33 3 0.80 0.30 0.66 ( 1 1 -1 1 3.35 1.25 0.026 min 80min 0min M M k slope M - - - - = = = - [ ] [ ] [ ] [ ] 1 1 1 1/2 -1 1 Starting concentration 0.67 Final concentration 0.5 .67 0.335 1 1 1 1 1.49 ; 3.0 0.67 0.335 Using graph, time to go from 1.5 to 3.0 68 10 58min o M x M M M R R M M - - - - = = = = = = = = - = [ ] [ ] [ ] [ ] ( 29 1 1 1/2 1 1 1 1 : ; 0.026 min 0.335 0.67 1.49/ 0.026 57min o Or solve kt M t R R t - - = + = + = =

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

View Full Document
7) Consider the following reaction: 3A(g) + B(g) C(g) + 4D(g). Suppose the concentration of A is 0.51 M and 12.0 s later, it is 0.39 M. What is the average rate of reaction for this time interval? 8) For the reaction D B + C, the rate constant, k, is 1.0 s -1
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• 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.

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

• 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.

Dana University of Pennsylvania ‘17, Course Hero Intern

• 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.

Jill Tulane University ‘16, Course Hero Intern