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Energetics and Thermodynamics

In the Decomposition Reaction of Gallium Chlorate...

5. In the decomposition reaction of gallium chlorate, 450 grams is heated, to produce oxygen and gallium chloride. Calculate the following: 1. Write the balanced equation for the reaction 2. Find the mole ratios of the reactants and products required to solve any stoichiometric problem 3. Find the mass in megagrams of ga

Aluminum Metal Volume

Alumminum metal melts at 660 degree Celsius and boils at 2450 degree C. Its density is 2.70 grams/cc. Calculate the following: the volume occupied by 15 milligrams of aluminum vapor at its boiling point and under a pressure of 1140 torr. the volume occupied by 100 kilograms of the metal at 25 C. If the specific heat ca

Various Calculations of Thermodynamics

1. At 25 degees C, (triange)H(little o) for the combustion of liquid octane, C8H18(l) to form CO2(g) and H2O(l) is -5471kJ/mol. Calculate (triangle)E(little o) for this reaction at 25 degrees C. 2. The molar heat of vaporization of benzene, C6H6, at 1 atm is 30.8 kJ/mol. The boiling point of benzene at 1 atm is 78.3 degree C.

Enthalpy Change

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

Enthalpy of vaporization of a liquid

The vapor pressure of a liquid in the temperature range 200 to 260K was found to fit the expression ln( P/torr) = 16.255 - (2501.8 / T/K) Calculate the enthalpy of vaporization of the liquid.

Electricity from nuclear power and coal

When some large nuclear plants run at full capacity, they produce about 1900 MW of electrical power. At this rate, what mass of 235U (kg) would it consume per year if the efficiency of converting nuclear energy to electricity is 33%? How many metric tons of coal would be required to supply the same amount of electricity?

The gaseous hydrocarbon acetylene, C2H2 is used in welders' torches because of the large amount of heat released when acetylene burns with oxygen, producing carbon dioxide and water.

1. The gaseous hydrocarbon acetylene, C2H2 is used in welders' torches because of the large amount of heat released when acetylene burns with oxygen, producing carbon dioxide and water. First, write a balanced equation fro the combustion of acetylene is oxygen. Then, how many grams of oxygen are needed for the complete combusti

Gibbs Energy of Mixing When the Partition is Removed

Consider a container of volume 5.0 L that is divided into two compartments of equal size. In the left compartment there is nitrogen gas at 1.0 atm and 25 degrees C; in the right compartment there is hydrogen at the same Temperature and Pressure. Calculate the entropy and Gibbs energy of mixing when the partition is removed. Ass

Gas-phase absolute entropy

1. Which molecule below should have the highest gas-phase absolute entropy at 25°C? a. CH4 b. H2 c. C2H6 d. C2H4 e. C2H2 2. Some standard entropies (at 25°C in J/mol K) are given: Ca2+(aq) -55.2, F-(aq) -9.6, CaF2(s) +68.87. ΔS° for the reaction CaF2(s)  Ca2+(aq) + 2F-(aq) at 25°C in J/K is ____

General Chemistry and Thermodynamics

7.5. Given the following table of thermodynamic data, substance ΔHf° S° POCl3 (g) -542.2 kJ/mol 325 J/mol - K POCl3 (l) -597.0 222 determine the normal boiling point (in °C) of POCl3. a. 133.0 b. 532 c. 273

General Chemistry - Law of thermodynamics

1. Which one of the following is a correct statement of the first law of thermodynamics? a. ΔS = q - T b.at absolute zero, for a pure crystalline solid, S = O c. ΔS >or equal q/T d. ΔH = ΣΔHproducts - ΣHreactants e. ΔE = q + w 2. A reversible process is one that ________. a. must be carried out at high

Thermodynamics and Triprotic Acid

1. Citric acid is a triprotic acid (represented by H3Cit). A student mixes together the following solutions in a styrofoam coffee cup: - 5.00 mL of 0.64 M citric acid - 45.00 mL of 0.77 M NaOH The two solutions start at a temperature of 26.0°C, and reach a final temperature of 27.9°C. The final, combined mixture has a mas

Thermodynamics and Specific Heat

You are given 10.0 grams of a mixture of NaNO3 and KF. You dissolve this mixture in 100.0 grams of water, and the temperature rises by 1.02°C. Calculate the mass of each salt in the original mixture. Assume that the specific heat of the solution is 4.18 J/g°C. Useful information: Enthalpy of solution of NaNO3: +20.5 kJ/mol

Thermodynamics and Enthalpy of Formation

I need some help with this problem, see attached file for full problem description with proper symbols: 2. a) Use only the following data to determine delta H°f for NO2 (g): - delta H°f for NO (g) is +90.4 kJ/mol - delta H = -56.6 kJ/mol for the reaction: NO (g) + 1/2 O2 (g) ---> NO2 (g) b) Find delta H for the reaction: 4

COLLIGATIVE PROPERTIES

1. I need help with the standard deviation/percentage error in the attached lab experiment. 2. Also need help graphing for the ethyl acelate and unknown solvent -- plotting negative delta T versus the total volume of solute that was added (2 graphs) and calculation of the slopes 3. I am not certain but I believe this ques

P chem

Calculate deltaS standard for the sublimation of CO2. The enthalpy of sublimation is delta H^0=25.23 kJ/mol at 195K. delta S^0= 1 ATM

Chemistry

1. In a free radical reaction, the following step would be categorized as CH3. + Br . ----------> CH3Br a. Initiation b. Propagation c. Substitution d. Termination 2. The heat of reaction (enthalpy change, delta H) for the following reaction is I2 + CH4 -----------> CH3I + HI a. 13 kcal/mol b. 140 kca

Activation Energy of Reaction

FOR THE REACTION CO + NO2 ------>CO2 + NO The activation energy for the forward reaction is 135 kj/mol of CO reacted. A) Determine the heat of reaction. B) From the data given and the enthalpy of reaction, determine the activation energy for the reverse reaction. C) Draw and label a potentia

Vapor Density & Ideal Gas Law

Please take a look at the attached lab report on vapor density. Please see the ** items regarding percentage error and calculation of R. I can't figure out how to do the percentage error of my trials and the calculations for the R values are confusing. Thanks for your help. --- Vapor Density and the Ideal Gas Law Lab Con

Enthalpy Change and Affecting Variables

Change in (delta) H degrees = 2816kJ 6CO2(g) + 6H2O (l) <->C6H12O6(s) + 6O2 (g) How is the equilibrium yield of C6H12O6 affected by: a. Increasing P CO2 (explain) b. Increasing temperature (explain) c. Removing CO2 (explain) d. Decreasing the total pressure (explain) e. Removing part of the C6H12O6 (explain) f. Addin

Amount of Ice Added to Cool Water

A quantity of ice at 0.0 degrees Celsius was added to 27.8g of water at 21.0 degrees Celsius to give water at 0.0 degrees Celsius. How much ice was added? The heat of fusion of water is 6.01 kJ/mol and the specific heat is 4.18 J/(g*C).

Energetics and Thermodynamics - Basic Chemical Equations

1. a. Calculate the [H+] of a weak acid solution with [OH-] = 3.50x10^-8M b. Calculate the pH of the solution c. Calculate the [H+] of a Classic Coke if the pH=3.75 2. Write the balanced equations: (Neutralizations) in ionic form and show net ionic equation. a. H2SO4(aq) + NaHCO3(aq)--> b. H3PO4(aq)+Mg(OH)2--> 3. Cal

Heating curve of solid

In a heating curve of a solid substance: Which phase (curve) would represent the heat of vaporization? Which phase (curve) would represent kinetic energy? Which phase (curve) would represent the melting point? Which phase (curve) would represent the phase change (s)? Which phase (curve) would represent the greatest increase

Heating Curve of solid subtance

In a heating curve of a solid substance: Which phase (curve) would represent the heat of vaporization? Which phase (curve) would represent kinetic energy? Which phase (curve) would represent the melting point? Which phase (curve) would represent the phase change (s)? Which phase (curve) would represent the greatest increa

Gases, Temperature, Current and Reactions

1) Calculate w and Delta E for the expansion of 20.0g of nitrogen gas from a volume of 30.0 L to a volume of 40.0 L at a constant 300.0K. 2) The density of ice at its normal freezing temperature is 0.917g/mL while that of liquid water at the same temperature is 0.9998 g/mL . If Delta H(fusion) of ice is 6.009 kJ/mol, what is

Heat energy and water

I have the data but I am having a hard time determining the end result. How much heat energy is required to raise the temp. of 5.0g of H20 from -10C to 110C ? (ice to steam) Given the following data: Specific Heat J/gK Molar Heat Capacity J/molK Formula Mass Water (l) 4.184

Dealing with Exothermic and Endothermic Reactions

I am in summer school and I missed both of these on my test and my final is cumulative and there will be questions like these on the final. 1. Sketch a diagram representing an exothermic reaction. Label both the horizontal and vertical axes. Show reactants and products, energy of activation and (delta Hrxn) on your sketch.