Questions
Explain why one can obtain eigenfunctions for the Hamiltonian operator for the H atom, but can...

Explain why one can obtain eigenfunctions for the Hamiltonian operator for the H atom, but can only obtain approximate wavefunctions for multi-electron atoms.

In: Chemistry

Consider the titration of a 44.3 mL sample of 1.145 M HC2H3O2 with 0.52 M NaOH....

Consider the titration of a 44.3 mL sample of 1.145 M HC2H3O2 with 0.52 M NaOH. Ka(HC2H3O2) = 1.8x10-5

Determine the pH at the equivalence point. Enter to 4 decimal places.

In: Chemistry

8. The two methods of determining pH values (pH indicator versus pH meter) should show similar...

8. The two methods of determining pH values (pH indicator versus pH meter) should show
similar pH values for those solutions. What was different?

In: Chemistry

If a buffer solution is 0.160 M in a weak acid (Ka = 1.0 × 10-5)...

If a buffer solution is 0.160 M in a weak acid (Ka = 1.0 × 10-5) and 0.470 M in its conjugate base, what is the pH?

In: Chemistry

State the Born-Oppenheimer approximation and describe how its use simplifies the description of Hamiltonian operator for...

State the Born-Oppenheimer approximation and describe how its use simplifies the description of Hamiltonian operator for quantum chemical calculations. [4 Marks]

By describing the underlying principles of Hartree-Fock theory and density functional theory, briefly compare and contrast the two methods.

In: Chemistry

Is there any other way we could obtain the concentration of the protein fractions other than...

Is there any other way we could obtain the concentration of the protein fractions other than using Bradford assay?

(Hint: Fluorescent proteins)

In: Chemistry

1.) Determine the initial concentration of a solution of the weak acid HClO2 , if it...

1.) Determine the initial concentration of a solution of the weak acid HClO2 , if it its pH is 1.20 and Ka = 1.10

In: Chemistry

Sulfurous acid (H2SO3) has Ka1 = 1.500 × 10-2 and Ka2 = 1.000 × 10-7. Consider...

Sulfurous acid (H2SO3) has Ka1 = 1.500 × 10-2 and Ka2 = 1.000 × 10-7. Consider the titration of 60.0 mL of 1 M sulfurous acid by 1 M NaOH and answer the following questions.

What is the maximum number of protons that can sulfurous acid ionize (per molecule)?

b) Calculate the pH after the following total volumes of NaOH have been added. (Correct to 2 decimal places.)   No marks will be given if the number of decimal places is wrong.

i. 0.0 mL of NaOH  

ii. 30.0 mL of NaOH  

iii. 60.0 mL of NaOH  

iv. 90.0 mL of NaOH

v. 120.0 mL of NaOH

vi. 130.0 mL of NaOH

In: Chemistry

The reaction of methane with water to form carbon dioxide and hydrogen is non-spontaneous at 298...

The reaction of methane with water to form carbon dioxide and hydrogen is
non-spontaneous at 298 K. Use the thermodynamic data from the table (it refers to 298 K) and determine at which temperature the system will make the transition from non-spontaneous to spontaneou

Substance:   CH4(g)    H2O(g)   CO2(g) H2(g)

ΔH° f (kJ/mol):   -74.87   -241.8    -393.5 0

ΔG° f (kJ/mol):   -50.81 -228.6 -394.4 0

S°(J/K·mol):   186.1     188.8   213.7 130.7

In: Chemistry

How does the coordination of an actinide at a given oxidation vary with the increase of...

How does the coordination of an actinide at a given oxidation vary with the increase of ionic radius of halides?

In: Chemistry

1) From the balanced molecular equations, write the complete ionic and net ionic equations for the...

1) From the balanced molecular equations, write the complete ionic and net ionic equations for the following. (Use the lowest possible whole number coefficients. Include states-of-matter under the given conditions in your answer.)

a) SnCO3(s) + H2SO4(aq) → SnSO4(s) + CO2(g) + H2O(l)

b) Sr(NO3)2(aq) + H2SO4(aq) → SrSO4(s) + 2 HNO3(aq)

c) K2C2O4(aq) + Pb(OH)2(aq) → 2 KOH(aq) + PbC2O4(s)

2) Indicate what type, or types, of reaction each of the following represents. (Select all that apply.)

(a) 2 KClO3(s) → 2 KCl(s) + 3 O2(g)

acid-base, combustion, double displacement, neutralization, oxidation-reduction, precipitation, single-displacement

(b) Sn(NO3)2(aq) + H2SO4(aq) → SnSO4(s) + 2 HNO3(aq)

acid-base, combustion, double displacement, neutralization, oxidation-reduction, precipitation, single-displacement

(c) C4H8O2(l) + 5 O2(g) → 4 CO2(g) + 4 H2O(g)

acid-base, combustion, double displacement, neutralization, oxidation-reduction, precipitation, single-displacement

(d) Al(OH)3(aq) + 3 HBr(aq) → AlBr3(aq) + 3 H2O(l)

acid-base, combustion, double displacement, neutralization, oxidation-reduction, precipitation, single-displacement


In: Chemistry

1. in what context do the terms hydrophobic and hydrophilic relate to the soulubilites of substance...


1. in what context do the terms hydrophobic and hydrophilic relate to the soulubilites of substance in water?
2. in each of the following pairs of compounds which compound is likely to be more souble in CC14?
(a) Br2 or NaBr
(b) CH3CH2OH or CH3OCH3
(c) Cs2 or KOH
(d) I2 or CaF2
3. which sulfur conpound would you predict to be more souble in nonpolar solvents: SO2 or CS2?
4. methanol has a larger molar mass than water, but boils at a lower temperature. Suggest a reason why?
5. How is it that the dipole moment of HCI(1.08D) is larger than the dipole moment of HBR (0.82D) yet HBR boils at a high temperature?
6. why is methanol miscible with water but methane is not?

In: Chemistry

In the qualitative analysis scheme, magnesium and nickel precipitate from solution upon the addition of sodium...

In the qualitative analysis scheme, magnesium and nickel precipitate from solution upon the addition of sodium hydroxide. Once separated from the remaining cations by filtration or decanting, the solid mixture is acidified and warmed to dissolve magnesium and nickel cations back into solution. Adding ammonia creates a buffer solution. (Remember, HCl and NH3 makes for NH4+ cation.) The buffered solution should just be basic (say, pH = 8). Adding sodium hydrogen phosphate (Na2HPO4) precipitates magnesium as MgNH4PO4 (Ksp = 3 x 10-13).

a)Write the dissociation equation and corresponding Ksp expression

b)Calculate the molar solubility of the compound

In: Chemistry

Part 1) Solvent trapping is used for a) analysis of trace components. b) analysis of high-boiling...

Part 1) Solvent trapping is used for

a) analysis of trace components.

b) analysis of high-boiling major components.

c) analysis of low-boiling major components.

Part 2) Open tubular columns of less than 0.53 mm in diameter:

a) cannot be used for on-column injection of analyte with a standard injection needle.

b) do not give resolution as good as that of wider columns.

c) are excellent when used with thermal conductivity detectors.

In: Chemistry

a chef prepares 350mL of simple syrup by dissolving 240g if sucrose (MW = 342 g/mol)...

a chef prepares 350mL of simple syrup by dissolving 240g if sucrose (MW = 342 g/mol) in 250mL of water (density = 1.0g/mL). calculate the concentration of sucrose in the resulting solution in each of the units below.

1. g/L

2. M (molarity)

3. m (molaity)

4. X (mole fraction)

In: Chemistry