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Energetics and Thermodynamics

Multiple choice questions on spontaneous reactions and maximum concentration

Calculate the maximum concentration (in M) of sulfide ions in a solution containing 0.181 M of lead ions. The Ksp for lead sulfide is 3.4 x 10-28. a. 1.9 x 10-27 b. 9.4 x 10-28 c. 1.5 x 10-26 d. 3.0 x 10-25 e. 3.4 x 10-28 A reaction that is spontaneous ___________. a. will proceed as written without outside interv

4 Dissolution/Solubility Questions

1. How much N2 can dissolve in water at 25'C if the N2 partial pressure is 585. Mm Hg? 2. Hexachlorophene is used in germicidal soalp. What is its molar mass if 0.640g of the compound, dissolved in 25.0 g of chloroform, produces a solution whose boiling point is 61.93 'C? 3. The enthalpy of solution of KClo3 in water is

Reverse process activation energy

3.) Show the reaction coordinate diagram (energy diagram) for the process in which the energy change of the reaction is -60 kJ, and the activation energy is 30 kJ. What is the reverse process activation energy?

Enthalpy of Calorimeter

What is the final temperature of a calorimeter in which 5.6g of copper at 354 K is put into 56.8 g of water at 22.4 degrees centigrade?

Absolute entropy, free energy and spontaneity

1) Describe in detail the difference in absolute entropy values for the following pairs: a) C(s, graphite) and C(s, diamond) b) HCl(g) and HCl(aq) c) CH4(g) and CH3CH2CH2CH3(g) 2) a) Calculate the values of DeltaH° and DeltaS° for the following reaction at 25°C. b) Use the values from a to calculate DeltaG° for the

Total Heat Calculation

From the data listed, calculate the total heat, in Joules, to convert 10.0 g of liquid ethanol at 55.0 C to gaseous ethanol at 95.5 C.

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.

FIVE-STEP SYNTHESIS

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.