Questions
Please answer these TRUE or FALSE questions. 1. True or False. The Born-Oppenheimer approximation accounts for...

Please answer these TRUE or FALSE questions.
1. True or False. The Born-Oppenheimer approximation accounts for scattering.
2. True or False. Tunneling is one way to approximate the solution to the Free Particle.
3. True or False. The coordinate version (x,y,z) of the Free Particle wavefunction can be normalized by including time.
4. The spin quantum number is used when combining the Hydrogen Atom and Free Particle models together.

In: Chemistry

What is the pH of a solution made by mixing 500 mL of 1.00 M HCN...

What is the pH of a solution made by mixing 500 mL of 1.00 M HCN and 1.50 L of 0.250 M NaOH, and then diluting the entire solution to a volume of 3.00 L? (Ka HCN = 4.0 x 10-10)

  • A.

    8.92

  • B. 6.52

  • C.

    9.88

  • D.

    9.27

  • E.

    5.08

To obtain one litre of a solution of pH = 7, you should dissolve in water

  • A.

    Two mol of HI + two mol of CH3NH2

  • B.

    One mol of H2SO4 + two mol of NH3

  • C.

    One mol of HF + one mole of KOH

  • D.

    Two mol of H2SO4 + four mol of NaOH

  • E.

    Two mol of H3PO4 + three mol of Ca(OH)2

In: Chemistry

The intermediate product of a chemical process is a chemical paste that is saturated with water....

The intermediate product of a chemical process is a chemical paste that is saturated with water. The paste is rolled into a thin layer and placed to dry in a flat area 30m long 15m wide. Drying is enhanced by blowing hot air over the paste, and the mass transfer coefficient is 0.017 m/s. Diffusion of water through the paste is rapid so that the concentration of water vapor at the surface of the paste remains constant at 0.002 gmol/L. Water must be removed from the paste remains at a minimum rate of 9.5 L/min (liquid volume). (Note:MW water=18 and p water=1 g/cm^3.)

a.) What mechanism controls the transfer of water from the paste in the air?

b.) What is the molar rate of water removal that corresponds to a volumetric removal rate of 9.5 L/min?

C.) What is the maximum concentration of water vapor allowable in the air (far from the paste surface) if water must be removed at a rate of at least 9.5 L/min?

D.) Assuming that the mass transfer coefficient remains constant, what can be done to increase the rate of water removal from the paste?

In: Chemistry

In a 0.57mM aqueous solution of trimethylacetic acid C4H9CO2H , what is the percentage of trimethylacetic...

In a

0.57mM

aqueous solution of trimethylacetic acid

C4H9CO2H

, what is the percentage of trimethylacetic acid that is dissociated? You can find some data that is useful for solving this problem in the ALEKS Data resource.

Round your answer to

2

significant digits.

In: Chemistry

1. Calculate the solubility of PbI2 in units of both moles x liters-1and g x(100mL)-1 using...

1. Calculate the solubility of PbI2 in units of both moles x liters-1and g x(100mL)-1 using your average Ksp value

Average Ksp= 7.40x10-7

                                    

2.      Explain why the solid PbI2 does not appear in the equilibrium expression for solubility.

3.      What effect would the use of KNO3 in Part III Step 4, instead of KNO2 have on the experimental absorbance values? Explain your answer.

In: Chemistry

A hot air balloon of 25 m in diameter has a mass of 95 kg including...

A hot air balloon of 25 m in diameter has a mass of 95 kg including its cage when empty. This balloon is accelerating upward at an acceleration of 1 m/s^2 in the air at a location where the atmospheric pressure and temperature are 85 kPa and 13 C respectively while carrying 3 people with a mass of 70 kg each. Determine the average temperature of the air in the balloon assume equal pressure between the inside of the balloon and its outside.

In: Chemistry

Determine the molar solubility of AgBr in a solution containing 0.150 M NaBr. Ksp AgBr =...

Determine the molar solubility of AgBr in a solution containing 0.150 M NaBr. Ksp AgBr = 7.7x10-13

In: Chemistry

Post-Lab Questions: Answer. 1. What should you examine to determine the precision of your results? Explain....

Post-Lab Questions: Answer. 1. What should you examine to determine the precision of your results? Explain. 2. What should you examine to determine the accuracy of your results? Explain. 3. If the standardization of the NaOH in Experiment 7 was not performed correctly and the experimental normality was too low, how would that affect the experimental equivalent weight being determined in this experiment? Would it be too high or too low? Explain. 4. You were allowed to weigh out between 0.35 g and 0.40 g of the unknown sample. If you used 0.35 g for Trial #1 and 0.40 g for Trial #2, would the experimental equivalent weight for Trial 2 be higher, lower or the same as that of Trial #1? Explain. ACID-BASE TITRATION Determination of the equivalent weight of an unknown acid.

In: Chemistry

4. If I use a catalyst, a. how will it change the reaction? b. if it...

4. If I use a catalyst,

a. how will it change the reaction?

b. if it is an equilibrium reaction, how will it change the equilibrium constant?

5. What happens to the equilibrium if I add some of the product to the beaker where the reaction is happening? How does the equilibrium shift? Is it gone forever?

In: Chemistry

For the diprotic weak acid H2A, Ka1 = 2.2 × 10-6 and Ka2 = 8.4 ×...

For the diprotic weak acid H2A, Ka1 = 2.2 × 10-6 and Ka2 = 8.4 × 10-9. What is the pH of a 0.0600 M solution of H2A? What are the equilibrium concentrations of H2A and A2– in this solution?

In: Chemistry

1a)  From the volume of titrant added, calculate the moles of vitamin C for each titration. Show...

1a)  From the volume of titrant added, calculate the moles of vitamin C for each titration. Show a sample calculation for trial 1, and then just state the final results for the calculation of trials 2 and 3. Use 5 digits in all intermediate values and report the final value to the appropriate number of significant figures.

Trial 1

Trial 2

Trial 3

b) From the results of question 1, calculate the average value for the number of moles of vitamin C titrated. Report the final value to the appropriate number of significant figures.

c) Calculate the precision for the mole values used to calculate the average in question 2.

Data table:

Trail1 Trail2 Trail3
Final buret reading 24.50 mL 48.80 mL 42.90 mL
Initial buret reading 0 mL 24.50 mL 18.32 mL
Volume of KlO3 24.50 mL 24.30 mL 24.58 mL

KlO3 concentration= 0.002012 M

In: Chemistry

A 10-L drum of ether at 18C is open to the atmosphere (p=760 Torr) and contains...


A 10-L drum of ether at 18C is open to the atmosphere (p=760 Torr) and contains 6-L of liquid. The top is sealed and the drum dented so that it now has an 8-L capacity.If the vapor pressure of the ether at 18C is 400 Torr, What is the pressure inside the dented sealed drum? Can you please show work and explain. Thanks

In: Chemistry

Part (a) The cyclopentadienyl anion (C5H5 - ) is commonly used aromatic ligand. The secular equations...

Part (a) The cyclopentadienyl anion (C5H5 - ) is commonly used aromatic ligand. The secular equations for describing the interactions of the five unhybridized p orbitals lead to a matrix of the form:

( ?11 − ??11 ?12 − ??12 ?13 − ??13 ?14 − ??14 ?15 − ??15
?21 − ??21 ?22 − ??22 ?23 − ??23 ?24 − ??24 ?25 − ??25
?31 − ??31 ?32 − ??32 ?33 − ??33 ?34 − ??34 ?35 − ??35
?41 − ??41 ?42 − ??42 ?43 − ??43 ?44 − ??44 ?45 − ??45
?51 − ??51 ?52 − ??42 ?53 − ??53 ?54 − ??54 ?55 − ??55)

where ??? is the Hamiltonian integral for orbitals ? and ? and ??? is the overlap integral for orbitals ? and ?. This matrix can be simplified using the approximations of Hückel molecular orbital (MO) theory, which involves two constants ? and ?.

(i) Explain the approximations of Hückel MO theory in terms of ??? and ???, and define ? and ?.

(ii) Re-write the above matrix applying these assumptions. [You may write this matrix (and only the matrix) on paper and copy and paste and image of it into your word document if you wish.] (iii) Briefly explain (without performing any calculations) how this matrix is used to determine the energies and coefficients of the MOs.

In: Chemistry

How does the absorption capacity of the regenerated activated carbon compare to that original activated carbon?...

How does the absorption capacity of the regenerated activated carbon compare to that original activated carbon? Explain why there is a difference.

In: Chemistry

what are some weak acids and weak bases? and how do conjugate acids and bases work?...

what are some weak acids and weak bases? and how do conjugate acids and bases work? how do i find what is a buffer and what is not a buffer?

In: Chemistry