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Physical Chemistry

Rate Constant with Temperature Changes

Rearrangement of methyl isonitrile to acetonitrile has activation energy of 25.0 kJ/mol and a rate constant of 8.1*10^-4s-1 @ 80 Celsius. what is the value of the rate constant @ 255.0 celsius?

Amount of natural gas burned is proportional

nt of natural gas burned is proportional to the amount of oxygen consumed. if 24.0 kg of oxygen is consumed in burning 15.0 kg of natural gas, how much air, which is 23.2% oxygen by weight, is consumed to burn 50.0 kg of natural gas? a. 80.0 kg b. 345 kg c. 31.3 kg d. 135 kg

Oxidation and reduction - arranging reactions in order

I am having trouble with this question: i) A reacts spontaneously with 1 mol/L BNO3, 1 mol/L D(NO3)2 and dilute sulfuric acid. A does not react with 1 mol/L C(NO3)2 ii) B does not react spontaneously with any of the 1 mol/L solutions above or with dilute sulfuric acid. iii) C reacts spontaneously with dilute sulfuri

Calculating pOH and pH.

Calculate the pOH and pH at 298K of solutions having the following ion concentrations: OH = 1.3 x 10^-2 M.

Calculate Energy Required to Heat Water

Calculate how much energy is required to heat 100 g of ice at 0 degrees Celsius to steam at 100 degrees Celsius. Draw a diagram of temperature versus time for water being heated. Heat of fusion of water = 6.02 kJ/ mole Heat capacity of liquid water = 4.18 J/degree Celsius x g Heat of vaporization of water = 40.7 kJ/ m

Calorimeters and heat capacity

If 2.500 g of Mg is burned in a constant volume calorimeter with a heat capacity of 1.10 kJ/degrees Celsius containing 1.500 L of water at 23.50 degrees Celsius and releases 37.33 kJ of heat, what is the final temperature of the calorimeter and water? Please show your work and solve. Thank you.

Smelters and Galena Conversion

A small smelter converts galena (lead sulfide) into pure lead by heating the ore with an excess of oxygen. Sulfur dioxide is produced as an air pollutant, as a result of the reaction. To remove sulfur dioxide, the flue gas is passed through a slurry of lime (calcium oxide) to produce calcium sulfate. The smelter processes 120

Mass balance

See attached for full problem. The concentration of isobutene in the overhead product is 4.8 mole %, and the concentration of propane in the bottoms is 0.7 mole %. Calculate the moles of the various components in the overhead and bottoms per 100 moles of feed.

Gibbs Phase Rule

What is the consequence (what does it mean?) when a system has zero degrees of freedom as calculated by the Gibbs Phase Rule? What do I need to conclude about such a system?

Chemistry Multiple Choice Quiz with Answer Grid

I am preparing for my chemistry exam and would appreciate a multiple choise quiz on the last chapter (i.e., ideal gas law, superconductivity, extensive properties, critical pressure, aerobic, etc.). Can you provide me with such a quiz with the answers provided. Thanks. Chemistry Quiz 2: Multiple Choice Questions 1) Eleme

Mass Balance Problem with Fuel

A furnace burns a fuel oil, the composition of which can be represented as (CH2) n. It is planned to burn this fuel with 10 % excess air. Assuming complete combustion, calculate the composition of the flue gas on a dry basis. Please see attachment for the rest of the problem, including relevant diagrams.

Fractional Composition

Derive the fractional compositions for monoprotic and diprotic systems showing the steps as clear as possible including a brief description of a fraction compostion plot. And if possible throw in examples, so I can understand it better.

Reduction through constant current electrolysis

Reduction through constant current electrolysis a) How much Cr3+ was reduced to Cr2+? b) A few seconds after the electrolysis was stopped, the potential of the cell came to rest at -0.524 volts. How much Cr3+ actually remains in the solution? c) What was the original Cr3+ concentration?

Adiabatic expansion

0.5 mol of an adiabatic monotonic ideal gas in a container at 250kPa and 350K is allowed to expand reversibly: Cv= (3/2)R Cp= (5/2)R If possible, find the final temperature, delta H, delta U, q, and w

Molecular weight and solution problem

The molecular weight of NaOH is 40. the molecular weight of a widely used buffer, HEPES, is 255. HEPES has a pK of 7.5 and is available in the acid form. how many grams og HEPES and NaOH are needed to produce one liter of a 0.5 molar solution of pH 7.5? of pH 7.0? of pH 8.5?

Find reactant and product information

Balance the following reaction: Mn + HCl --> MnCl2 + H2 If you have 100g of Mn and 100g of HCl find a. The limiting reageant b. Moles of MnCl2 formed c. Grams of MnCl2 formed d. Moles of excess reagent

Partial molar volumes at given temperatures and pressures

The molar volume (cm^3 mol^-1) of a binary liquid mixture at T and P is given by: V = 120x1 + 70x2 + (15x1 + 8x2)x1x2 (a) Find expressions for the partial molar volumes of species 1 and 2 at T and P. (e)Plot values of V, partial V1, and partial V2 calculated by the given equation for V and by the equations developed in (a) vs. x

Triple point

The sublimation pressures of solid chlorine are 352 Pa at -112 C and 35 Pa at -126.5 C. The vapor pressures of liquid Chlorine are 1590 Pa at -100 C and 7830 Pa at -80C. Calculate a)heat of vaporization b)heat of sublimation c)heat of fusio d)triple point I have already figured out the first three. The heat of sublimation

Working with heat of vaporization

I have attached the graphs. I don't think the first one is useful, but i needed to plot the data and find the heat of vaporization. Hence, the reason for the second graph. I know that the slope is equal to the heat of vaporization/RT but I don't think I am getting the right answer.

Statistical Mechanics Vibrational Temperatures

2. Given the vibrational temperature of HCl is 4227 K, a) what is qvib at a temperature of 2600 K, keeping the zero point energy? and referenced to v = 0? b) what is qvib at a temperature of 3100 K, keeping the zero point energy and referenced to v= 0? c) What is the vibrational contribution to CV, at the temperature 2600 K

Working with partition function and entropy

1. Given the rotational temperature of HCl is 15.02 K, a) what is the ratio of the number of particles in the J= 14 to the J=4 level at a temperature of 1900 K? b) What J level has the highest proportion of particles at the temperature 1900 K? c) What is the energy, E, of rotation at this temperature? d) What is the entr

Finding expressions for Partial Molar Values

The molar volume (cm^3 mol^-1) of a binary liquid mixture at T and P is given by: V = 120x1 + 70x2 + (15x1 + 8x2)x1x2 (a) Find expressions for the partial molar volumes of species 1 and 2 at T and P. (b) Plot values of V, partial V1, and partial V2 calculated by the given equation for V and by the equations developed in (a) vs