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Energetics and Thermodynamics

Calculating percent yield in a reaction

A chemist ran the reaction CH3CH2Cl(l) + KOH(aq) ^ CH3CH2OH(l) +KCL(aq) by heating 47.2 grams of CH3CH2Cl with excess KOH and obtained a yield of 28.7 grams of CH3CH2OH. What was his % yield? I do not know where to begin with this problem. It only gives grams of one reactant? What is the actual yield? Detailed step by step in

How conditions alter rate of enzyme-catalyzed reaction

How will each of the following changes in condition alter the rate of an enzyme-catalyzed reaction: -decreasing temp to 10 deg C? -increasing the pH of the solution from 7 to 11? -heating only the enzyme to 100 deg C?

Calculate delta G; temperature; pressure

Kp is 1.0x10-3 atm-1/2 at 2000K and delta S at standard temperature and pressure = 87.864 J/K mole (delta Cp = 0) for the reaction CO2(g) yielding CO(g) + 1/2 O2(g) (this reaction is reversible) (a) Calculate delta G at 2000K, (b) Calculate delta G at standard temperature and pressure at 298K, and (c) Calculate the degr

Reactions and Mechanisms

(1) Which member of each pair of reactions occurs the most rapidly and by what mechanisms? a. i. (CH3)3CCH2Cl -- CN-, ethanol --> ii. PhCH2Cl -- CN-, ethanol --> b. i. CH3CH2CH2CH2Br -- CN-, (CH3)2N)2PO --> ii. CH3CH2CH2CH2Br -- CN-, CH3OH --> c. i. (CH3)3COH -- H30+, 25 degrees Celsius --> ii. CH3CH2CH2CH2OH -- H30

Enthalpy Change Cycles

10. Look at the enthalpy cycle below... a) What enthalpy change is represented by delta H1? b) What are the combined enthalpy changes represented by delta H2? c. What enthalpy change is represented by delta H3? d. write and equation that links delta H1, delta H2, and delta H3. e. use the answers from parts a and d and the f

Heat Capacity and Combustion of Isopropyl Alcohol

The combustion of isopropyl alcohol occurs according to the following reaction: C3H7OH (l) + 9/2 (g) ----> 3CO2(g) + 4H20 (g) How much work is done if 1 mole of isopropyl alcohol is burned at a temperature of 298k and 1 atm. pressure? Give your answer in the following units: (a) L- atm, (b) J and (c) KJ. If the heat

Description of Heat Capacity

Calculate the specific heat capacity of benzene(C6H6), given that 192 J of heat is required to raise the temperature of a 20.0g sample of benzene from 25.2 C to 38.8 C. What is the molar heat capacity of benzene? (the molar heat capacity is the heat capacity of 1 mole of benzene) 3.50 Kcal of heat is removed from a 1.50 Kg

Endothermic Reaction

THE ENDOTHERMIC REACTION A(g) + B(g) 2C(g) PROCEEDS TO AN EQUILIBRIUM CONDITION AT 200 CELSIUS. WHICH OF THE FOLLOWING STATEMENTS IS (ARE) TRUE? 1- If the mixture is transferred to a reaction vessel of twice the volume, the amounts of reactants and products will remain unchanged 2- Addition of an appr

Activation energy and milk

At room temperature (20 C), milk turns sour in about 64 hours. In a refrigerator at 3 C, milk can be stored 3 times as long before it sours. At each temperature, the constant K: K= c/(souring time) where c is a constant. 1. Estimate the activation energy of the reaction that causes the souring of milk 2. How long

Alkane formula, endothermic reactions, and calculating volume

Question 26 The general formula of an alkane is: CnH2n CnH2n+2 CnH2n-2 CnH2n+4 CnH2n-4 Question 27 Endothermic reactions cause the surroundings to cool down heat up become acidic increase electromagnetic radiation Question 28 In the compound 2-iodo-4-nitrom

Activation Energy

For the reaction CO+NO2>CO2+NO the activation energy for the forward reaction is 135 kJ/mol of CO activated. a) Determine the heat of reaction. b) From the data given, and the ^Hr for the reaction, determine the activation energy for the reverse reaction.

Moles Produced from Heating

1. How many moles of carbon dioxide will be produced if 50g of potassium hygrogen carbonate are heated? 2. Also, What is the mass of one nitrogen molecule (in grams). Do they mean N_2_? Thanks! : )

Synthesis scheme for ibuprofen and compound found in poppies

Papaverine is a morphine-like compound found in poppies. It can easily be synthesized from the Amide A. Show the synthesis scheme of Amide A starting with the substituted benzene starting material below. Show a synthesis scheme for ibuprofen (Advil®) starting with benzene

Delta Heat for a Reaction

Evaluate Delta H (standard) for the reaction below at 25 degress celcius SiO2 (s) + 4HF (aq) >>>>>>> SiF4 (g) + 2H2O (l) Delta H standard f (kj/mol) -910.9 -320.8 -1615 -285.8

Heat (in Kj/mol rxn) Absorption in This Reaction

How much heat is absorbed in the complete reaction of 3.00 grams of SiO2 with excess carbon in the reaction below? Change in H degrees for the reaction is +624.6 kJ. SiO2 (g) + 3C (s) >>>>>>> SiC (s) + 2CO (g)

Solubility and Gibbs Free Energy Questions

1. Firstly, how do you calculate the molar solubility of AgBr when given 0.1 M AgBr at 25 degrees C (Ksp = 5 x 10^-3)? If show me a few examples of how to calculate molar solubility when you're given different things, I would appreciate it. 2. Next, how can I calculate the squilibrium direction of CO2 at 25 degrees C and 9

Heat Related Problems

Hi, I need some assistance with the following questions: 1) You have two pieces of Al metal - one is a thin piece of Al foil, and the other is a thick block. Both have the same length and width. Which will absorb more heat when set on a hotplate for the same period of time to raise the temperature 5 degrees? a) Block b) Fo

Final Temperature (Compare Substances)

You place 2 beakers at 25 degree C on a hot plate Beaker A = 100.0mL Beaker B = 100.0mL Each absorbs 15.0 Kj of heat. A) What is the final temp of each liquid? B) Why would one liquid be hotter than the other?

Heat and Heats of Formation

The question states: Given 2BaCO3(s) ---> 2Ba(s) + 2C(s) + 3O2(g) Change in H = 2432.6kJ First they ask for me to determine the heat of formation of BaCO3. My problem is how do you determine the heat formation of the reactant (in this case) when you are given a change in H for the whole thing. Secon

Calculating energy and cost for solar heater

The average home has a 200 liter (50-60 gallon) hot-water tank, which is effectively drained and replenished three times per day. Assume that the entering tap water is 16 degrees C and is heated to 56 degrees C. Given an average energy from sunlight of 1.53 kJ/cm^2 per day, how large would the collection area (in m^2) of a solar

Understanding Gibbs Free Energy Change

What is Gibbs free energy? What is the difference between entropy and enthalpy? What does the useful work derived do such that the entropy increases (additional to that increased along with enthalpy) but enthalpy remains the same (i.e the useful work does not increase the enthalpy)?


Provide a retrosynthetic and forward analysis for the following molecule, starting from commercially available compounds. The retrosynthesis should clearly identify the synthons and their synthetic equivalents. Also functional group interconversions and bond disconnections should be clearly indicated where needed. The forward

Vapor pressure and boiling point solution

This is a question about finding boiling point of water with the vapor pressure formula. The question states In Breckenridge, Colorado, the typical atmospheric pressure is 520 torr. what is the boiling point of water (delta Hvap = 40.7 kJ/mol) in Breckenridge? Using the vapor pressure formula Do we pick the ln(P1/P2)=

Enthalpies of Vaporization

To vaporize a 1.50 g sample of liquid benzene C6H6 requires 652 J of heat. What is change of heat vapn of benzene in kilojoules per mole?

delta H of vaporization

Plot the following vapor pressure data to determine the delta H vaporization of the compound. Plot 1/T (in Kelvins) vs ln(VP) in atmosphreres and get the enthalpy of vaporization from the best fit line. T in degree Celsius 188 227 258 313 VP (Torr) 10.0 40.0 100.0 400.0

Solution and Solvent Problems

1. Calculate the molality of a solution of 14.0 g of Mn(NO3)2 in 250 g of water. 2. Calculate the molarity of a solution made by taking 60.0 mL of 2.79 M. NaOH and diluting it to a final volume of 260mL. 3. A natural alcohol has been isolated by an ethnobotanist working in the Amazon. A solution of 6.38 g of this alcoho

Extent of reaction as function of temperature

If given the change in entropy and the change in enthalpy, derive an expression for the extent of the reaction as a function of temperature. Please look at the attached diagram for an adequate description.

Determining the Efficiency of a Water Heater

Some of the butane, C4H10(g), in a 200.0 liter cylinder at 25.0 degrees C is withdrawn and burned at a constant pressure in an excess of air. As a result the pressure of the gas in the cylinder falls from 2.35 atm to 1.10 atm. The liberated heat is used to raise the temperature of 132.5 liters of water from 25.0 to 62.2 degree