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Energetics and Thermodynamics

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

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

Change in Free Energy: Combustion

Calculate change in Gdegree for the combustion of ethanol vapor, C2H5OH(g), at 750degree C in oxygen to form carbon dioxide and water vapor. The following data is valid at 25 degree C: Changein H degree(KJ/mol) change in Gdegree(KJ/mol) C2H5OH(g) -234.8 -167.9 O2(g) 0 0 H20(g)

Auto-ionization of Water

Kw for the auto-ionization of water, H2o(l) -> H positive(aq) + OH negative (aq) is 1.0 x 10 to the negative 14. Calculate deltaGdegree,DeltaSdegree and DeltaHdegree for the reaction at 25 degree C?

Decomposition of Nitrosyl Chloride

Nitrosyl chloride (NOCl) decomposes at elevated temperatures according to the eqation 2 NOCl(g) <-> 2 NO(g) + Cl2(g) Calculate Kp for this reaction at 227 degrees C. For this reaction change in Hdegree =81.2 KJ/mol, change in Sdegree= 128 J/K x mol

Oxygen and Spontaneous Reactions

The element oxygen was prepared by Joseph Priestley in 1774 by heating mercury oxide: HgO(s)->Hg(l) + (1/2)O2(g) delta H = 90.84 KiloJoule/mol S(Hg)=76.02 J/K x mol S(o2)=205.0 J/K x mol s(HgO) =70.29 J/k x mol Estimate the temperature at which this reaction will become spontaneous under standard state conditions.

Calculating Heat of Combustion

The DH of combustion of CH4 is -882kJ/mol.How many grams of water, which has a specific heat of 4.184 J/g-oC can be heated from 30oC to 95oC by the heat produced in the combustion of 2.25 mol of CH4?

Calorimetry and work

One mole of water evaporates in an open container at 273 Kelvin. The formula is H20 liquid---->>>>H20 gas. What is the work done on or by the system? a. 2.3 kJ b. -2.3 kJ c. 22kJ d - 22kJ

Inorganic Thermodynamics

Calculate the standard enthalpy of formation of gaseous diborane, B2H6, using the following thermochemical information: (See attachment for full question)

Inorganic Chemistry Midterm Study Guide

Please do all of the midterm. These are the sections that will be covered in our midterm please complete with long explanations as well as giving related info to questions asked. Thanks.

Heat Loss and Specific Heat

a) A student wishes to determine the specific heat of a metal using a coffee cup calorimeter (calorimeter constant 50.35 cal/degrees Celsius). The student heats 130.56 grams of unknown metal from 25.0 degrees Celsius to 100.4 degrees Celsius. The initial temperature of the calorimeter (coffee cup plus 30 mL water) was 23.5 degre

Work of expansion

One mole of nitrogen gas confined within a cylinder by a piston is heated from 9.1°C to 883.6°C at 1.30 atm. Calculate the work of expansion (include sign) in joules (1 J = 9.87à?10-3 atm L). Assume all of the energy is used to do work.