Questions
Calculate the vibrational energy difference, in cm-1, between the v=0 and v=1 energy level in a...

Calculate the vibrational energy difference, in cm-1, between the v=0 and v=1 energy level in a hydrogen chloride-35 molecule. Isotope masses to three decimal places are taken from NIST and force constants from hyperphysics. Use the isotope mass, not the average mass.

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Two structures of alanine can be drawn that have a net charge of zero, but the...

Two structures of alanine can be drawn that have a net charge of zero, but the predominant form of alanine at its pI is zwitterionic. Why is alanine predominantly zwitterionic rather than completely uncharged at its pI? What percent (to one significant figure) of alanine molecules would be in the completely uncharged form at the pI? Hint: pK1 of alanine is 2.35 and pK2 is 9.87.

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A) A 29.0 mL sample of 0.274 M methylamine, CH3NH2, is titrated with 0.238 M hydroiodic...

A) A 29.0 mL sample of 0.274 M methylamine, CH3NH2, is titrated with 0.238 M hydroiodic acid.

The pH before the addition of any hydroiodic acid is ______.

B) A 24.5 mL sample of 0.220 M ethylamine, C2H5NH2, is titrated with 0.399 M hydroiodic acid.

At the titration midpoint, the pH is ______.

C) A 28.2 mL sample of 0.293 M dimethylamine, (CH3)2NH, is titrated with 0.273 M hydrochloric acid.

After adding 13.6 mL of hydrochloric acid, the pH is ______.  

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Calculate the concentration of all species in a 0.150 M solution of H2CO3. H2CO3], [HCO−3], [CO2−3],...

Calculate the concentration of all species in a 0.150 M solution of H2CO3. H2CO3], [HCO−3], [CO2−3], [H3O+], [OH−] = Enter your answers numerically separated by commas. Express your answer using two significant figures.

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Explain precipitate hardening clearly ? Feel free to use a binary phase diagram to illustrate how...

Explain precipitate hardening clearly ? Feel free to use a binary phase diagram to illustrate how it is accomplished. Explain how precipitate hardening makes a material stronger and harder ? There are two reasons and only one is pinning of dislocations ?

Please type your answer!!! Thanks

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Part A Calculate the molar solubility of Ni(OH)2 when buffered at pH=8.0. Express your answer using...

Part A

Calculate the molar solubility of Ni(OH)2 when buffered at pH=8.0.

Express your answer using one significant figure.

Part B

Calculate the molar solubility of Ni(OH)2 when buffered at pH = 10.3.

Express your answer using one significant figure.

Part C

Calculate the molar solubility of Ni(OH)2 when buffered at pH = 12.0.

Express your answer using one significant figure.

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At –80°C, K for the reaction N2O4(g) 2NO2(g) is 4.66 × 10–8. We introduce 0.049 mole...

At –80°C, K for the reaction N2O4(g) 2NO2(g) is 4.66 × 10–8. We introduce 0.049 mole of N2O4 into a 1.0-L vessel at –80°C and let equilibrium be established. The total pressure in the system at equilibrium will be: (0.78 atm)

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In the first 12.0 s of the reaction, 1.6×10−2 mol of O2 is produced in a...

In the first 12.0 s of the reaction, 1.6×10−2 mol of O2 is produced in a reaction vessel with a volume of 0.340 L . What is the average rate of the reaction over this time interval?

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In the first 12.0 s of the reaction, 1.6×10−2 mol of O2 is produced in a...

In the first 12.0 s of the reaction, 1.6×10−2 mol of O2 is produced in a reaction vessel with a volume of 0.340 L . What is the average rate of the reaction over this time interval?

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The questions below refer to the following system: Co(H2O)6 2+ + 4 Cl– CoCl4 2– +...

The questions below refer to the following system: Co(H2O)6 2+ + 4 Cl– CoCl4 2– + 6H2O pink blue

When cobalt(II) chloride is added to pure water, the Co2+ ions hydrate.

The hydrated form then reacts with the Cl– ions to set up the equilibrium shown here. 27.) What change will the system undergo if hydrochloric acid is added? (It should become more blue and the equilibrium will shift to the right.)

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A mixture containing 15.0 mol% hexane balance N2 flows through a pipe at 6.53 kmol/h. The...

A mixture containing 15.0 mol% hexane balance N2 flows through a pipe at 6.53 kmol/h. The pressure is 2.00 atm (abs) and the temperature is 100°C. If I want to begin to condense the hexane, what temperature do I need cool to? If I want to condense 80% of the hexane, what temperature do I need to cool to?

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Show that the following are eigenfunctions of the Laplacian operator and determine the eigenvalues: a. (r^-1)sinkr...

Show that the following are eigenfunctions of the Laplacian operator and determine the eigenvalues: a. (r^-1)sinkr

b.( r^-3)[(sin^2)θ]sin2φ

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1.A sample of nitrogen at 20.0 °C has a volume of 954 mL at a pressure of 1,101 mmHg. To change the volume to 1,496 mL, what must be the new pressure?

 

1.A sample of nitrogen at 20.0 °C has a volume of 954 mL at a pressure of 1,101 mmHg. To change the volume to 1,496 mL, what must be the new pressure?

2. A sample of nitrogen has a volume of 4.65 L at 1,639 mmHg and 51 °C. What volume will it occupy at standard temperature and pressure?

3. A sample of O2 gas with a volume of 6.43 L was collected at 278 °C. What is the volume of the gas if the temperature is changed to 99 °C at constant pressure?

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an unfortunate effect of drinking too much alcohol, known as a hangover, is attributable to the...

an unfortunate effect of drinking too much alcohol, known as a hangover, is attributable to the acetaldehyde formed when ethanol is oxidized. there is some evidence that vitamin b1 can cure a hangover. how can the vitamin do this? Can I see a mechanism

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1. You work for a crafts supply company, KidKrafts, making calcium carbonate for their chalk products....

1. You work for a crafts supply company, KidKrafts, making calcium carbonate for their chalk products. They have recently decided to add plaster of Paris as one of their products. The key ingredient in plaster of Paris is calcium sulfate (CaSO4). You have been asked to adapt your knowledge of making calcium carbonate from calcium chloride dihydrate (CaCl 2 •2H2O ) and anhydrous sodium carbonate (Na2CO3) to making calcium sulfate. To make the most profit, you will be using the same stock of calcium chloride dihydrate as for the chalk. Therefore, you need to make sure that you use only the necessary amounts of each reactant. Your boss has asked you to not only figure out how to make the calcium sulfate but to prove that you don’t have any excess of either reactant.

a. The first step is figuring out what you need to mix together to make calcium sulfate. You know that the combination of calcium chloride and sodium carbonate worked well to make calcium carbonate in lab. Propose one chemical that you could react with calcium chloride to make calcium sulfate.Give two reasons why the chemical you chose will work. (Hint: What can you replace sodium carbonate with to make calcium sulfate instead of calcium carbonate?)

b. Now that you’ve selected a reactant, write out its (a) complete and (b) net ionic reaction with calcium chloride. You can ignore the waters of hydration on calcium chloride for this step.

c. If you run the reaction above using a solid mixture of exactly the right amount of each reactant, how can you prove that there is no excess? Describe the steps involved with this test. (Hint: Think about how you determined which reactant was in excess in the lab.)

d. Since you are developing a new procedure with a new chemical, you need to check how will you store it at the lab. Look up the MSDS of the reactant you proposed. What does your boss need to keep in mind when storing this chemical?

e. To try out your reaction and test for correct amount, you first need to determine how much of the reactants you need. What mass of your proposed reactant will you need to react with 1.000 g of calcium chloride dihydrate?

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