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Energetics and Thermodynamics

Bromine entropy of vaporization

Hi, Please explain this as ELEMENTARY as possible. Bromine is one of the only two elements that is liquid at room temp. Bromine has a heat vap of Hvap = 30.91kJ/mol and its boiling point is 59EC. What is the entropy of vaporization for bromine?

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?

Gibbs Energy Question

Calculate deltaG of reaction for: glucose+ 2 ATP ----> 2 ADP + 2 G3P For concentrations, glucose: 5.0 mM G3P:0.019 mM ATP: 1.85 mM ADP:0.14 mM delta G for reaction under standard conditions = -1.97 kJ, assuming the temperature is 298 K. Do I use delta G standard + RT ln K for this reaction? What is T in th

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

Equilibrium and Change in Pressure

NOBr in a 1.1 g quantity is placed in an evacuated 1 liter flask at -55 degrees C. The flask is warmed to 0 degrees C where the gaseous contents exert a pressure of 0.3 atm (all species are gaseous). At 25 degrees C, the equilibrium total pressure rises to 0.35 atm. What is Kp at 0 degrees C and 25 degrees C? What is delta H (as

Solve: Clausius-Clapeyron Equation

Question: The vapor pressure of ethylene is given as a function of temperature by the equation: log p = (-834.13/T) + 1.75logT-8.37* 10^-3T+5.323 Calculate delta Hvap of ethylene at its normal boiling point (-103.90C).

Enthalpy Change

Hydrogen peroxide decomposes according to the following thermochemical reaction: H2O2(l) --> H2O(l) + 1/2 O2(g); Delta H = -98.2 kJ Calculate the change in enthalpy, Delta H, when 1.00 g of hydrogen peroxide decomposes.

Heat Transfer QUantity

Which of the following DOES NOT have an impact on heat transfer quantity across a surface? A. Surface area B. Process fluid type C. Temperature of process fluid D. None of the above

Enthalpy change

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

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 app

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! : )

Calculating delta G

I am trying to understand how to balance this equation. We were given the following data to solve for delta G (standard). S(s) + 3/2 O2(g)--------->SO3(g) delta G standard = -371kJ 2SO2(g)+ O2(g)--------->2SO3(g) delta G standard = -142kJ Now calculate delta G standard for the reaction. delta G standard = d

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

Solve this Standard Heat of Reaction Problem

Given the standard heats of formation for the following compounds, calculate the change H2 degrees 98 for the following reaction: CH4 (g) + H2O (g) >>>>>> CH3OH (l) + H2 (g) Change in H Degree F (kj/mole) -75 -242 -238 0 I need to see how to solve this, and most importantly, the answer.

Lattice Energy of MgO

Write the reaction involved with lattice energy for MgO. Class example said steps to find delta E is 1) Write formation for reaction, 2) Form gases to elements, 3) dissociate diatomics, 4) remove electrons from cation, 5) add electrons to anion, 6) form solid.

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


A] What type of calorimetry is used to determine the heat evolved by burning a gummy bear (promarily glucose) B] If the gummy bear weighs 1.25g and the temp of the calorimeter increases by 50 degrees C how much heat is absorbed / released by the reaction?

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?

Calorimetry - Final Temperature

I just need to know the formula for this problem I cannot find it in my book. If you have 2.40 mol of Au at 100 degrees C and is added to 10.mol of water at 25 degrees what will be the final temp...cpAu=25 J/Km and cp of water=75.3J/Km. Thanks

Activation energy

I am trying to find deltaH. The activation energy is 128kJ for this reaction. The activation energy for the reverse reaction is 95kJ. In the presence of a catalyst Eacat is 110kJ.

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

Saturated and Supersaturated Solutions

Take a saturated solution, for example, let's use salt water. At room temperature, you totally saturate the solution. Then, you slowly heat the solution, and suddenly you can add more. Does this make it a super saturated solution? Also, once you take the solution back down to room temperature, will salt crystals reappear i

Calculating Calories of Heat Produced

a) If 5.0 moles of H2 react, how many calories of heat are produced? (Using the bal equation: N2 + 3H2 -> 2NH3 + 21941 calories) b) How many grams of H2 are needed to produce 55.0 grams of NH3? c) Is this reaction endothermic or exothermic?