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Over time, BPB converts to a colorless molecule in the presence of OH¯ ions. To study the rate of the reaction, the student recorded the absorbance of the BPB solution at 590 nm in a 0.50 M NaOH solution. The temperature and [OH¯] remain constant throughout the reaction. The results are summarized in the table below. Time Absorbance (min) 0.60 4 0.48 8 0.38 12 0.30 16 0.24 20 0.19 24 0.15 (f) Determine the half-life of the reaction. Include units with your answer. (g) Explain how the absorbance and time data are consistent with a process that is first order with respect to BPB. A second trial is conducted at the same constant temperature, but with [OH] changed to 2.00 M. The observed half-life of the reaction is shorter than for the first trial when [OH¯]was 0.50 M. (h) Explain, in term of particle collisions, why the half-life of the reaction decreases when [OH¯]is changed from 0.50 M to 2.00 M. (i) Is the activation energy for the reaction when [OH¯]is 2.00 M greater than, the same…

The rate law of a reaction is given below.From the given rate law, what will happen to the reaction time and reaction rate if the concentration of one of the reactants is doubled while keeping everything the same? why?Also, why the starch solution used as an indicator in an experiment turned blue at the end of the reaction?

Another common component of reaction mechanism is a catalyst. These are compounds that change the reaction mechanism and provide a pathway with a lower activation energy, and correspondingly faster reaction rate. They are a reactant in an early step in the mechanism and a product in a later step. They do not appear in the overall reaction but do appear in the rate law. 3. A reaction occurs by the following mechanism; Step 1 Ce4+ + Mn²+ →→ Ce³+ + Mn³+ Step 2 Ce4+ + Mn³+ → Ce³+ + Mn²+ Step 3 Tit+ Mn+→ Ti³+ + Mn²+ a. Write the overall reaction. b. Identify each of the components as a reactant, product, intermediate, or catalyst; Mn²+ Mn³+ Ce4+ Ce ³+ Mn4+ Tit Ti³+ C. Assuming that the catalyst is involved in the rate determining step, what is the rate law for this reaction? 4. Under certain conditions, the reaction: 2 NO + Cl₂ → 2 NOCI is found to be second order in NO and first order Cl₂. Given the following mechanism; Step 1 NO + Cl2 → NOCI₂ Step 2 NOCI₂ + NO 2 NOCI a. What are the…

Write two differences between ‘order of reaction’ and ‘molecularity of reaction’.

How do you calculate the concentrations using the absorbance?

The rate constant of a certain reaction is known to obey the Arrhenius equation, and to have an activation energy E=7.0 kJ/mol. If the rate constant of this -D1 -1 reaction is 2.6 x 10´ Msat 343.0 °C, what will the rate constant be at 411.0 °C? Round your answer to 2 significant digits. =1 M x10

How was Thin Layer Chromatography (TLC) used in organic synthesis reactions ? TLC is used to find the exact concentration of a catalyst in the reaction. TLC can speed up a reaction because silica gel is polar. TLC can separate components of a reaction mixture such as starting materials and products allowing the experimenter to identify what compounds are in the reaction mixture. TLC is used to find percentage yield of the reaction.

Two kinetics trials are performed at the same temperature with [S2O82-] held constant. The first trial has a reaction time of 84 seconds. For the second trial, the [I-] is four times that of the first trial (the concentration is quadrupled), and the reaction time is 22 seconds.  How long would you expect the reaction to take if the trial used [I ̶ ] equal to one-half of the concentration used in the first trial?

Using knowledge about Biophysical Chemistry (Thermodynamics and Kinetics ).How can you determine whether a reaction mechanism you predict is consistent with the experimental data? What factors would cause you to throw out your proposed mechanism and try again?

What is the difference between order of reaction and molecularity ?

Hand written solutions are strictly prohibited.

(a) Select all of the correct statements about reaction rates from the choices below. The lower the rate of a reaction the longer it takes to reach completion.Reactions involving very unstable combinations of chemicals have large rate constants.Concentrations of homogeneous catalysts have no effect on reaction rates.Reaction rate constants are independent of temperature.The slowest step in a reaction is called the rate-determining step.A balanced chemical reaction is necessary to relate the rate of reaction to the concentration of a reactant.Slow reactions can be speeded up by raising the temperature.

For the gas phase isomerization of cis-1,2-diphenylethene, cis-C6H5 CH=CHC6H5 → trans-C6H5 CH=CHC6H5 the rate constant at 569 K is 2.11 × 10-4 s¯¹ and the rate constant at 608 K is 2.39 × 10 -3 S The activation energy for the gas phase isomerization of cis-1,2-diphenylethene is | s-¹. S kJ.

In aqueous solution buffered at a pH of 6.75 Penicillin G (molecular weight of 334.39 g/mole) undergoes hydrolysis via a pseudo first order reaction that has an activation energy of 77.3 kJ/mole and a pseudo first order rate constant of 1.58 x 10-7 s-1 at 30°C. The solubility of the sodium salt of Penicillin G is 25 mg/ml of water. One would expect the solubility of the sodium salt to be ____________ that of the Penicillin G.  a. higher than b. the same as c. lower than

Route 1:RME = 82.92%MI= 1.34 Route 2RME = 93.33%MI = 1.57 Route 3RME = 57.34%MI = 1.89 Compare the value of Reaction Mass Efficiency (RME) and Mass Intensity (MI) generally, and choose which metrics is more significant in green measurement. Justify your answer.

An unknown inorganic phosphate undergoes first-order dehydration in a drying oven. Initially, the excess water content is measured to be 1.13 mg. After 2.10 days the water content is reduced to 0.488 mg. After 4.40 days, water content is only 0.194 mg. Determine the half-life of hydration under these conditions.

The data below were collected for the following reaction: CH3CI(g) + 3 Cl2(g) CCI4(g) + 3 HCI(g) Trial [CH3CI] / mol L-1 [Cl2] / mol L-1 Initial Rate / mol L-1 s-1 1 0.050 0.050 0.0142 2 0.100 0.050 0.0290 3 0.200 0.200 0.115 What is the rate constant?

The rate constant of a certain reaction is known to obey the Arrhenius equation, and to have an activation energy E= 11.0 kJ/mol. If the rate constant of this -1 reaction is 8.1 x 10° M -1 at 253.0 °C, what will the rate constant be at 296.0 °C? Round your answer to 2 significant digits. -1 -1 x10

A study of the rate of dimerization of C4H6 gave the data shown in the table: 2C4H6→C8H12 Time (s) [C4H6] (M) 0 1.00 x 10–2 1600 5.04 x 10–3 3200 3.37 x 10–3 4800 2.53 x 10–3 6200 2.08 x 10–3 What is the instantaneous rate of dimerization at 3200 s? Create a graph of time versus [C4H6] to help answer this question.   Question 1 options:   a)  9.4 x 10-7 M s-1   b)  8.2 x 10-7 M s-1   c)  7.7 x 10-7 M s-1   d)  6.5 x 10-7 M s-1

The rate law for the reaction H2(g) + 2NO(g) → N2O(g) + H2O(g) was experimentally determined to be rate = k [NO]2 [H2]. Which of the following statements is false? Doubling the concentrations of both reactants would double the reaction rate Tripling H2 concentration would triple the reaction rate The overall reaction order is 3 Decreasing NO concentration by half would decrease the reaction rate 4 times

With a starting concentration of 4.00 x 10^-3 M ClO2, how much time (in s) will it take up for the compound (ClO2) concentration to reach 1.20 x 10^-3 M? See the image for the given table.

1.) The anticancer drug cis-platin hydrolyzes in water with a rate constant of 1.5 ×10−3 min−1 at pH 7.0 and 25°C. Calculate the half-life for the hydrolysis reaction under these conditions. If a freshly prepared solution of cis-platin has a concentration of 0.053 M, what will be the concentration of cis-platin after 5 halflives? after 10 half-lives?   2.) Ethyl chloride decomposes to ethylene and HCl in a first-order reaction that has a rate constant of 1.6 × 10−6 s−1 at 650°C. What is the half-life for the reaction under these conditions? If a flask that originally contains 0.077 Methyl chloride is heated at 650°C, what is the concentration of ethyl chloride after 4 half-lives?

In aqueous solution buffered at a pH of 6.75 Penicillin G (molecular weight of 334.39 g/mole) undergoes hydrolysis via a pseudo first order reaction that has an activation energy of 77.3 kJ/mole and a pseudo first order rate constant of 1.58 x 10-7 s-1 at 30°C. What would the value of the rate constant be (in s-1) if the temperature was 60°C?  a. 9.96 x 10-9 b. 1.59 x 10-7 c. 2.51 x 10-6 d. 7.62 x 10-6 e. None of the above

TIUL Water to avoid burns. Be sure to wear safety goggles while performing the experiment. Part A In this task, you'll observe a chemical reaction between baking soda and vinegar in water. Write a hypothesis to predict the relationship between the concentrations of the reactants and the rate of the reaction. В I U x' Font Sizes 三 三 星川 三三 A - As the vinegar becomes more diluted, the reaction will become less. Characters used: 67 / 15000 V O 10:40

ÇF3 ÇF3 NANH. NH3 (-NaCI) NH,Write the mechanism of the reaction

но HO HO HO 0 + ½ O, → + H,0 H H но он ascorbic acid dehydroascorbic acid Vitamin C is oxidized slowly to dehydroascorbic acid by the oxygen in air. It is catalyzed by ions such as Cu*2 and Fe*3. The reaction can be followed by measuring the ultraviolet absorbance at 243 nm. Time (hours) Absorbance (A) 1/A In A - In A 0.75 1.3 -0.29 0.29 1 0,38 2.6 -0.97 0.97 2 0.19 5.3 - 1.7 1.7 3 0.095 11 - 2.4 2.4 28. A new compound is synthesized and found to be a monoprotic acid with a molar mass of 248 g/mole. When 0.0050 moles of this acid are dissolved in 0.500L of water, the pH is measured as 2.94. What is the pKa of this acid? (A) (B) (C) (D) 2.33 3.89 5.78 7.78 29. What is the hybridization of carbon 1 (far left) and carbon 2 (middle) in this hydrocarbon: CH3CH=CH2? (A) sp³, sp (B) sp?, sp? (C) sp³, sp? (D) sp, sp?