Kinetics Definition and 234 Threads

1. Hello there, I am a first year undergraduate mechanical engineering student, looking for help on a question. "Figure Q2 shoes a schematic diagram for an aircraft catapult system. The aircraft is represented by the mass A (Ma), and μ is the coefficient of friction between the aircraft and...

Homework Statement Four point masses form a rigid body (they are connected by massless rigid rods) given the positions M1= 3kg (2m, 4m, 0m) M2= 2kg (1m, -4m, 0m) M3= 1kg (10m, 2m, 0m) M4= 5kg (-5m, 2m, 0m) Find: A) Moment of inertia of this system when it rotates about x axis B) Moment of...

My textbook (Burdge, Chemistry, 2nd edition) is pretty vague mathematically when it comes to calculating the examples, so I'm a bit confused about solving this example problem. The equation is fairly straightforward: ln{[A]_{t}/[A]_{0}}=-kt The 14.4 problem statement is (paraphrased)...

Equilibrium constant vs rate constant - where kinetics meets thermodynamics?? The Equilibrium Law for aA + bB ⇌ cC + dD gives Kc = [C]c [D]d / [A]a x [B]b at a given temperature. Kc* is also equal to the ratio of forward to reverse rate constants kfwd/krev. The rate expression for the forward...

Homework Statement The mean life of a certain radioactive element is 6 hrs. By what fraction will its initial activity decrease over a time period of 5 hrs. Homework Equations t_{avg}=\frac{1}{k} Initial Activity = kN_{0} Final Activity = kN_{t} The Attempt at a Solution From eqn 1...

1. question http://farm9.staticflickr.com/8282/7804721900_bd0b895954_b.jpg On a catalyst surface, the formation reaction of CO2 by the oxidation of CO with O2 proceeds in the following mechanism. (1) O2(g) + 2V <---> 2O(ads) (equilibrium constant KO2) (2) CO(g) + V <--> CO(ads)...

Homework Statement A top is a toy that is made to spin on its pointed end by pulling on a string wrapped around the body of the top. The string has a length of 64 cm and is wrapped around the top at a place where its radius is 2.0 cm. The thickness of the string is negligible. The top is...

Homework Statement So the question says for the reaction 2N2O5(g) --> 4NO2 (g) + O2(g) provides a linear plot when P(N205) is plotted against t with a negative slope . The decomposition of N2O5 follows ? Homework Equations The Attempt at a Solution I am guessing that P(N205) is...

The correct answer states its C which i understand why since doubling the intiial volume of SO2 is equivilent to doubling the intial moles of SO2 hence the moles of SO3 produced will also increase and hence pressure exerted shld be higher than before which is not reflected by the graph...

The problems are Number 12 and 13 on this link http://isites.harvard.edu/fs/docs/icb.topic1096438.files/PS4.pdf I have the value of k for sum number 12, it is 1.54*10^-4. Im completely stuck with number 13 cos I'm unfamiliar with that concept and it kinda went over my head in lecture...

I am studying the activation energy of a reaction, and I notice that it says when the products are more stable than the reactants the reaction is exothermic, and endothermic when the products are less stable than the reactants. It doesn't say why, but my supposition is that when the products...

Homework Statement The tension answer I got is different from the answer. Can someone help me take a look at my working? Really appreciate your time in doing this. Thanks alot.

Homework Statement Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate lnKU = ln KU H20 - m ku [denat] when the concentration of denaturant is above that needed to unfold 50 % of...

1. Folding can be described as transition between the native and unfolded state. In increasing concentrations of denaturant, a fold disintegrates with a rate lnKU = ln KU H20 - m ku [denat] when the concentration of denaturant is above that needed to unfold 50 % of protein. Conversely...

Homework Statement http://img39.imageshack.us/img39/3778/funkyrider.jpg So I got this funky rider that starts its movement from the top of the hill A at initial speed (Vo). From that point, the bicycles role on freely (without using pedals) at the circular path. Calculate the velocity...

Simple kinetics problem / Dynamics / Simultaneous equations I've been trying to solve this problem for hours, not finding the solution. Therefore this question to PhysicsForums homeworks section. Question is just part of the problem, but in order to fully understand issue I must have these...

Homework Statement http://img42.imageshack.us/img42/8172/carxp.jpg Homework Equations In my solution The Attempt at a Solution My attempt: http://img208.imageshack.us/img208/6526/xxxxoh.jpg The actual solution http://img403.imageshack.us/img403/5579/carsol.jpg...

Homework Statement A hoop is released from rest at the top of a plane inclined at 16 above horizontal. How long does it take the hoop to roll 16.4 m down the plane? Homework Equations The Attempt at a Solution I know I have to find the final velocity, I know the Inertia is =...

1)A rock is dropped off a cliff and falls the first half of the distance into the ground in t1 seconds. If it falls the second half of the distance in t2 seconds, what is the value of t2/t1? Relevant equations: I think the kinematics equations of d=vt+(1/2)at^2 I have no idea how to solve...

Homework Statement I trying to do this hibbeler question which I have modified a bit However I'm not getting the correct answers which is supposed to be t=17.5 and t=11.3 s I will take a picture of my attempt when I get a hold of a camera in the meantime if anyone knows how to do it I...

For the questions below, which kinematic equations would I use? I have already tried these on my own but can not find a way to match the answers with the answer sheet, the answers on the answer key are RIGHT, as they are approved by my teacher. Okey so the questions are 1) A baseball is...

Hi everyone Homework Statement I got the three different diagramms (attached below) and I shall find a general chemical equation for all of them. Homework Equations - The Attempt at a Solution I think I know how to do the third one, but I have troubles with the first...

\begin{align} \dot{x} =& -x + ay + x^2y\notag\\ \dot{y} =& b - ay - x^2y\notag \end{align} The only steady states are $(-b,0)$ and $\left(0,\frac{b}{2a}\right)$, correct? I feel like there should be more but I don't think there any.

2NO + 2H2 --> N2 + 2H2O The concentration of NO is 0.006 M and the concentration for H2 is 0.002M. How can I find the concentration of NO remaining when one-half of the original amount of H2 has been consumed? if you can also show me how it would be done if the reaction was not 1:1, that...

We are currently going over Kinetics in my AP Chemistry class but I am struggling with kinetics, our book is not very clear and tackles on several ideas at once making it hard to understand. My teacher is also not very helpful, sadly. I have been searching for some notes on Kinetics but have not...

Hi guys, Got a general question here about sum of forces that keeps coming up for me, and so I want to try and nail it this time. If you have a pully system, and there is a weight attached to a rope at one end of say 10 kg and the other end is is attached to a force of 1000 N that is...

Homework Statement The rotor of an electric motor of mass 200 kg has a radius of gyration of 150 mm. Calculate the torque required to accelerate it from rest to 1,500 rev/min in 6 seconds. Friction resistance may be neglected. Homework Equations ƩMO = Iα I = 1/2 (mr2 I am really really...

Homework Statement At 25 C a catalyzed solution of formic acid produces 44.6 ml of carbon monoxide gas in 30s. a) Calculate the rate of reaction with respect to CO(g) production. Homework Equations Rate = dC / dT The Attempt at a Solution dC should be expressed in mol/L but I...

Homework Statement 2HCl + Na2S2O3 -> 2NaCl +S + SO2 + H2O Find the order of reaction with respect to S2O32- and H+ volume of 3.0M HCl was held constant at 2ml Homework Equations S2O32- + 2H+ -> S + SO2 + H2O rate = k[Na2S2O3]m[HCl]n (see number 3.) The Attempt at a Solution i just...

Somebody please help me. Practical: A calibration graph should be prepared by taking 0.0 (zero, blank), 1.0, 2.0 and 3.0 ml aliquots of an aqueous solution containing both 1.67 mM D-glucose and 1.67 mM D-fructose. Add distilled water to maket it 3 ml. Add 1 ml DNS reagent. Incubate 5 min...

Howdy all, Recently I have dabbled in homebrewing mead and it turned out... drinkable at best. I am making another batch soon and want to improve my methods. I am a nuclear engineering student, so naturally I feel that something as personal, liberating, and chemically miraculous as...

hi, My instructor has given us an assignment where we have to diagnose the type of enzyme inhibition it is. I diagnosed it as a competitive inhibitor and am trying to do a slope replot to find my value for KI. For the slope replot, you just find the slope of the each line? is it the same...

I've got nothing mates. Any help would be great.

Homework Statement The concentration of the reactant A has been studied as a function of time. By a suitable plot of the data below, show that the reaction is first order, and determine the rate constant, k, and the half-life, t1/2. Use the integrated rate equation to determine [A] when t =...

A 35N hand and forearm are held at a 45 degree angle to the vertically oriented humerus. The centre of gravity of the forearm and hand is located at a distance of 15cm from the joint centre at the elbow, and the elbow flexor muscle attach at an average distance of 3cm from the joint centre. How...

Homework Statement The acceleration of a body is defined as a=-K*u^2 , K is const. When t=o sec V=Vo. Find : a) V(t) b) X(t) c) V(x) . Homework Equations The Attempt at a Solution

Question 1: Step 1: 2NO2 (g) + 2SO2 (g) = 2NO (g) + 2SO3 (g) Step 2: 2NO (g) + O2 (g) = 2NO2 (g) The reaction is found to be first order with respect to NO2 and SO2, what is the slow step for this reaction? 1. First step 2.Second step 3.Not possible to determine Question 2 and 3...

hey guys, please see the attachment for the question. i drew FBDs and everything. i want to know a few things tho. how do i calculate the tension in the pulley? if they'd given me acceleration i could have used T-mg =ma. but they havent. also once the Tension is found, do i just find the...

Hello, I need help on this following problem on velocity/acceleration 1. Homework Statement The velocity function (in meters per second) is given for a particle moving along a line. v(t)=3t-11, 0 (greater than or equal to) t (greater than or equal to) 5 Find the distance (in meters)...

Homework Statement I am considering the reaction 2C4H6 --> C8H12 at 320 degrees C. Both the product and the reactant are gases. I have the data: Time (minutes): 0.00 3.25 12.18 24.55 42.50 68.05 Total P (torr): 632.0 618.5 584.2 546.8 509.3 474.6...

Hi I wonder if anyone could help me with this. I'm studying a crystal whose luminescence is excitonic in nature. Since the excitation density is high (with femtosecond laser pulses) exciton-exciton interactions have to be taken into account. The following kinetic equations are used to...

I need some help with the equation of moments for this exercise: Each wheel of an automobile has a mass of 22 kg, a diameter of 575 mm, and a radius of gyration of 225 mm. The automobile travels around an unbanked curve of radius 150 m at a speed of 95 km/h. Knowing that the transverse distance...

1.The 2-Mg truck is traveling at 15 m/s when the brakes on all its wheels are applied, causing it to skid for a distance of 10 m before coming to rest. Determine the constant horizontal force developed in the coupling C, and the frictional force developed between the tires of the truck and...

Hi All, I tried to collected hydrogen gas generated from the reaction between a metal and hydrochloric acid. I put a inverted conical flask in the water, and the generated H2 would push the water out of the flask, and then the H2 was collected. However, I guess there is water vapor mixed...

In my textbook there is an example with the following reaction and rate: C6H6 + 3H2 -> C6H12 Rf = kf[C6H6][H2] Then the the example claims that the ratio of the rate constants is: kf / kr = [C6H12] / ( [H2]3 [C6H6] ) How is the denominator of that ratio possible if the forward...

Homework Statement The 2Mg (i assumed mega-gram, not sure if that is the correct term) car has a velocity of v= 100km/h when the driver sees an obstacle in front of the car. If it takes 0.75 s for him to react and lock the brakes, causing the car to skid, determine the distance the car...

Homework Statement A 500kg crate is pushed with a 2000N force. The force of the sliding friction acting on the crate is 1900N. How fast will the crate be moving after 10 seconds? How far will it have moved in this time? Determine the net force Homework Equations a = \SigmaF/m...

Homework Statement Consider a first order decomposition reaction 2P(g) -----> 4Q(g) + R(g) + S(l) taking place at a temperature T. After 30 minutes from the start of the decomposition in a closed vessel, the total pressure developed is found to be 317 mmHg and after a long time, the...

So, let's say we have an elementary reaction: 2A --> C The rate of this reaction is (according to IUPAC: http://goldbook.iupac.org/R05156.html) - \frac{1}{2} \frac{d[A]}{dt} = k [A]^2 If we integrate this we get a certain integrated rate law (second order) However, if we multiply all of...

Homework Statement Our chemistry teacher just learned about chemical kinetics. I've been working with the calculus teacher to find out how to determine instantaneous rates exactly. We don't have any equation. Could someone explain this please? Homework Equations The Attempt at a...