Can you change this sentence so I dont get caught for plagerizm In the presence

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Can you change this sentence so I dont get caught for plagerizm

In the presence of hydroxide ion, CV undergoes a change to a colorless carbinol as shown above. Therefore the reaction can be studied by monitoring the color change at a selected wavelength. The absorption spectrum and molar absorptivity of CV have been determined and the absorption maximum occurs at 590 nm.

In this experiment, the kinetics of hydrolysis of crystal violet in basic solution are studied at 298K. The order of reaction, specific rate constant, and dependence of the rate on ionic strength are determined. Since the dye is colored, a convenient way to determine the reaction rate is to monitor the absorbance of the dye as a function of time. Carrying out the reaction in large excess [OH- ], a technique called isolation (or flooding) assures that the concentration of the OHremains constant throughout each kinetics experiment (run). Under these circumstances the changes in absorbance at the wavelength maximum in the dye absorbance spectrum give the time dependence of the dye concentration. From these data the order of reaction with respect to the [CV] can be deduced.

If the [OH- ] is present in high enough excess concentration, then it can be assumed that [OH- ] is approximately constant during the course of the experiment.

Thus, the logarithm of the concentration versus time is a linear function of the time with [CV]o equal to the initial concentration at time zero (as the OH- is being added to the reaction vessel) and slope equal to keff. If the graph of ln A vs. t is not linear then we can conclude the reaction is not first order in [CV]. In this case, use the data to plot ( l/[CV ]) vs. time.

The linearity of such a plot would indicate a second order dependence on [CV]. If this plot were nonlinear, we would try a third order dependence. When a pseudo-first-order reaction is carried out at a number of different excess initial concentrations of hydroxide [OH-]o , the order of the reaction in hydroxide (y) can be determined from a graph, and the specific rate constant for the reaction can also be calculated.

Explanation / Answer

When OH- is present, CV undergoes a reaction as shown above. It forms a colorless carbinol. Since there is change in color, the reaction can be studied by onserving and recording the color change at a selected wavelength. The molar absorptivity and absorption spectrum were calculated for CV and bsorption maximum was found to occur at 590 nm.

In this experiment, the kinetics of hydrolysis of crystal violet is studied in basic solution at 298K. The following are determined by this reaction:
a.order of reaction
b.specific rate constant
c.dependence of the rate on ionic strength

The colored dye is used to determine the reaction rate. The absorbance of the dye as a function of time was monitored. When reaction is carried out in excess [OH- ], the concentration of the OH- doesn't change and it assumed to remain constant throughout each kinetics experiment (run). So changes in absorbance at the wavelength maximum in the dye absorbance spectrum give the time dependence of the dye concentration. Once these datas are obtained , order of reaction with respect to the [CV] can be deduced.

Now use the data to plot ( l/[CV ]) vs. time. If the plot of logarithm of the concentration versus time is linear function of the time with slope equal to keff. If the graph of ln A vs. t is not linear then we can conclude the reaction is not first order in [CV].

If linaerty is observed, it will indicate a second order dependence on [CV]. If linearity is not onserved, try a third order dependence.

Since here OH- is in large excess, it is a pseudo-first-order reaction. When such a reaction is carried out at a number of different excess initial concentrations of hydroxide [OH-]o ,graph can be used to determine the order and specific rate constant of the reaction.

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