1. N

    theoretical rate

    Can anyone please tell me what is the theoretical rate for the reaction between Sodium thiosulphate and Hydrochloric acid. I have to find percentage error using the formulae: measured value - true value _______________________ x 100 true value thanks in advance
  2. T

    Rate equations

    Hi, I need some help with the rate equation in the attachment. I can see that [A] is first order but when I try to calculate [B] it comes up as a decimal. Any ideas? thanks
  3. J

    Calculate ppm of CO2 in seawater from flow rate?

    This is likely a simple calculation but I'm not sure exactly how to do it. I'm injecting pure CO2 at at a rate of 35 ml/min into seawater which has a flow rate of 6000 ml/min and want to calculate a predicted dissolved CO2 in seawater in ppm. Anyone know how to do this off hand?
  4. C

    Rate Law Problem

    The reaction of tert-butyl bromide with azide ion in aqueous solution is proposed to proceed by the following mechanism: (CH3)3CBr(aq) ⇌ (CH3)3C+(aq) + Br–(aq) where k 1 is the forward reaction and k -1 is the reverse reaction (CH3)3C+(aq) + N3–(aq) -> (CH3)3CN3(aq) k2 is the rate constant...
  5. C

    Chemistry Olympiad Rate Law Problem

    The reaction of tert-butyl bromide with azide ion in aqueous solution is proposed to proceed by the following mechanism: (CH3)3CBr(aq) ⇌ (CH3)3C+(aq) + Br–(aq) where k 1 is the forward reaction and k -1 is the reverse reaction (CH3)3C+(aq) + N3–(aq) -> (CH3)3CN3(aq) k2 is the rate constant...
  6. G

    rate law and mechanism

    Rate Laws and Mechanisms? The reaction and rate law for the gas-phase decomposition of dinitrogen pentaoxide are* 2N2O5(g) → 4NO2(g) + O2(g)* rate = k[N2O5]* Which of the following are valid mechanisms for the reaction?* 1.* N2O5 ⇌ NO3(g) + NO2(g) [fast]* NO2(g) + N2O5(g) → 3NO2(g) + O(g)...
  7. C

    How to predict reaction rate of catalytic redox of hydrogen

    In a fuel cell hydrogen is split into protons and electrons catalytically, usually with platinum. If hydrogen fuel is flowing over the catalyst, how can I predict the number of reactions that will occur? I'm most interested in how it depends on the surface area of the contact between the...
  8. S

    Reaction Rate

    Hi! 1) What is the meaning of initial rate of reaction? 2) Why is the order of reaction important in the study of reaction rate?
  9. G

    Rate Constant Problem

    Question in the link. How do I go from here and get the rate constant and n values?
  10. S

    Rate of Reaction (Iodine Clock) Experiment

    Hello :) Can somebody please provide me with some assistance to this question? I have attached an image to verify what I mean, but for our Iodine Clock practical we have to design a procedure similar to Part A for Part B but Iodide ions are now the variable and Peroxydisulfate is the constant...
  11. S

    Rate of Reaction, Activation energy and Equilibrium constant relations

    Rate of reaction - How fast a reaction goes to completion Activation energy - the amount of energy to get initiate a reaction EQC - Ratio of concentrations @ equilibrium (when the forward rate = reverse rate of reaction) Just needing some clarification on a certain example. "Because Ea is...
  12. S

    Finding initial rate

    Ok so I know you have to compare a concentration of a reactant that changes and the other stays constant. comparing experiment 1 and experiment 3 for NO , the concentration increases by 4 and the initial rate increases by ~4.01. I would estimate that to be an order of 1. Likewise for cl2...
  13. S

    Rate question

    Ok so the first one I think is 2 since [A]^1 [B]^2 and asks for ratio of A to B so .5/.5^2 equals 2. For the last part, I got [2.70] to [2.70]^2 and I got .3703. Am I doing these right? I appreciate any insight!
  14. S

    Rate of appearance

    For a), the reaction rate is: -delta[NO3]/delta t = -delta[NO]/delta t = 1/2 delta [NO2]/delta t I took half of -21.52x10^4 and got -107600 which is wrong for b) the rate is : -1/2 delta[NO3]/delta t = 1/2 delta[NO]/delta t = delta [O2]/delta t I thought since both NO3 and NO2 had 1/2 that...
  15. P

    Reaction Rate Laws vs. Pressure

    Hey guys, So, my Chemistry teacher gave us a test, and one of the questions sparked heated debate among every student in the class. The question asked "What is the affect on "k" when increasing pressure?" The equation we were dealing with was Rate = k [A] [B]. Now, I understand increasing...
  16. P

    Reaction Rate Laws of Bleaching

    So, I am working on my chemistry post-lab report and I'm having some difficulty with the math portion. Here is a quick run down of the experiment. We performed 2 experiments, (Reaction 1 and Reaction 2). Rxn 1: Mix 1mL dye, D.I. water and NaOCl into vile & measure absorption/time Rxn 2: Mix...
  17. S

    reaction rate & graph interpretation

    Hi everyone, I am revising Higher Chemistry at the moment and I have hit a bit of a stumbling block with part (b) (ii) of the question (from a past paper) in the image below. My attempt is (reading from the graph) 165.00-164.86 = 0.14g but this is incorrect and I know the answer should be...
  18. T

    Rate if reaction?

    I want to find how rate of reaction between hydrochloric acid and sodium thiosulfate varies with increasing concentration of sodium thiosulfate. I took 5 different concentrations of thiosulfate and reacted with hydrochloric acid (same concentration) and measured time. Then I plotted 1/time...
  19. L

    Rate constant

    Is it correct that the rate constant is 2,5 M^-1·m^-1 ? I have calculated this by reading the graph, go 1 to the right and 0,5 up. 1 to the right is equal to 25 mints and 0,5 up equals to 0,1. Then i multiply 0,5 with 25 =2,5 2,5 M^-1·m^-1 See attached file, thanks in advance is it also...
  20. L

    Struvite overall linear growth rate function of the concentration of ammonium

    Hi everybody, I would like to know if it is possible to write the overall linear growth rate of struvite crystals (MgNH4PO4.6H2O) as follow : G=L/(3.Vp.ρc) dm/dt = L.M.V/(3.Vp.ρc) d[NH4-N]/dt (adapted from M.I.H. Bhuiyan, D.S. Mavinic, R.D. Beckie, Nucleation and growth kinetics of struvite in...