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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.

Sign of Delta S

1. Predict the sign of delta S for the following reaction. Please explain the reason for your prediction. HgS(s) + O2(g) yields Hg(l) + SO2(g)

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.


Carry out a FIVE-STEP SYNTHESIS using a reaction from AT LEAST FOUR BOXES, and any other reaction that you know of anything at all, starting from one molecule having SEVEN carbons and one chiral center, and adding anything with FIVE or fewer carbons in each step (YOU WILL MOST LIKELY ADD NO CARBONS IN AT LEAST ONE OF THE STEPS).

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?

Determine the Enthalpy for the Reaction

Use the thermochemical equations shown below to determine the enthalpy for the reaction: 2Fe3O4(s) + 1/2O2(g)=>3Fe2O3(s) 6Fe(s) + 9/2O2(g)=>3Fe2O3(s) H=-1387.4KJ 6Fe(s) + 4O2(g)=>2Fe3O4(s) H=-1256.6KJ

Thermochemical Equations

Use the thermochemical equations shown below to determine the enthalpy for the reaction: Fe3O4 + CO(g)=>3FeO(s) + CO2(g) 2Fe(s) + 3CO2(g)=>Fe2O3(s) + 3CO(g) H=5.7KJ 2Fe3O4(s) + CO2(g)=>3Fe2O3(s) + CO(g) H=9.7KJ FeO(s) + CO(g)=>Fe(s) + CO2(g) H=0.3KJ

Calculating the Enthalpy Change

Calculate the enthalpy change of the reaction CH4 (g) + 2Cl2(g)  CCl4 (l) + 2H2 (g), using thermochemical equations: a) C(s) + 2Cl2 (g)  CCl4 (l)  = -128 kJ b) CH4 (g)  C(s) + 2H2 (g)  = + 75 kJ

Enthalpy Change of a Reaction

Calculate the enthalpy change of a reaction using the following values, enthalpy of reactant 1 = 404 kJ, enthalpy of reactant 2 = 432 kJ, enthalpy of product 1 = 218 kJ, enthalpy of product 2 = 74 kJ and enthalpy of product 3 = 199 kJ.

Calculating the Enthalpy Change for the Reaction

Calculate the enthalpy change for the reaction, NaCl + water  NaOH + HCl. Using the given values, the sum of the enthalpies of NaCl and water = 293 kJ and the sum of the enthalpies of NaOH and HCl = 162 kJ.

Standard Enthalpy Change

Calculate the standard enthalpy change of a reaction using the total enthalpies of the reactants and the products. The total enthalpy of the reactants is -912 kJ and the total enthalpy of the products is -82 kJ.

Thermochemical Enthalpy Changes

Calculate the enthalpy change of the reaction 2CO(g) + 2NO(g)  2CO(g) +N(g) using thermochemical equations: a) 2CO(g) + O(g)  2CO(g) b) 2NO(g)  N(g) + O(g) The enthalpy of the equation a) is -566.0 kJ and the enthalpy of the equation b) is -180.6 kJ.

Finding specific heat of gold

When a 50.0-g nugget of pure gold is heated from 35.0°C to 50.0°C, it absorbed 5200.0 J of energy. Find the specific heat of gold.

Calculate the Pressure

Step by Step explanation Ferrous oxalate, FeC2O4, will decompose on heating: FeC2O4 (s) ® FeO (s) + CO2 (g) + CO (g) A 1.25-gram sample of FeC2O4 is added to an evacuated 2.00-liter steel vessel. The vessel is heated to 400°C, at which point all the FeC2O4 is decomposed. Calculate the pressure inside the vessel at 400

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

Gibbs free energy and reaction

Given the Ka for HCLO is 3.0*10^-8, calculate delta G standard, at 25 degrees C, for : H30+(aq) + ClO-(aq) --> HCLO(aq) + H2O(l)

Free energy and entropy

For a certain complexation reaction, K=10^17. What are the signs of delta H standard, delta S standard and delta G standard for the equation from which the K expression is derived?

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

Lithium Iodide Solution

When lithium iodide is dissolved in water, the solution becomes hot. If an aqueous solution of LiI together with additional solid LiI were heated, would some of the solid dissolve or would more solid precipitate? I am very confused as to what this means and I can't find anything that really explains it in my book.

Enthalpy Change in a Calorimeter

You mix together the following solutions in a coffee-cup calorimeter: - 100.0 mL of 0.200 M CsOH - 50.0 mL of 0.400 M HCl Both solutions start out at 22.50°C, and the final temperature after reaction is 24.28°C. The densities of the solutions are all 1.00 g/mL, and the specific heat of the mixture is 4.2 J/g°C. Calculat