Questions
How do I identify HOMO and LUMO when given orbitals

How do I identify HOMO and LUMO when given orbitals

In: Chemistry

A 1.000-mL aliquot of a solution containing Cu2 and Ni2 is treated with 25.00 mL of...

A 1.000-mL aliquot of a solution containing Cu2 and Ni2 is treated with 25.00 mL of a 0.05832 M EDTA solution. The solution is then back titrated with 0.02380 M Zn2 solution at a pH of 5. A volume of 18.49 mL of the Zn2 solution was needed to reach the xylenol orange end point. A 2.000-mL aliquot of the Cu2 and Ni2 solution is fed through an ion-exchange column that retains Ni2 . The Cu2 that passed through the column is treated with 25.00 mL 0.05832 M EDTA. This solution required 23.22 mL of 0.02380 M Zn2 for back titration. The Ni2 extracted from the column was treated witn 25.00 mL of 0.05832 M EDTA.

How many milliliters of 0.02380 M Zn2 is required for the back titration of the Ni2 solution?

In: Chemistry

Silver bromide is used to coat ordinary black-and-whitep hotographic film, while high-speed film uses silver iodide....

Silver bromide is used to coat ordinary black-and-whitep hotographic film, while high-speed film uses silver iodide.

(a) When 96.0 mL of 5.0 g/LAgNO3 is added to a coffee-cup calorimeter containing 96.0 mL of 5.0 g/L NaI, with both solutions at 25°C,what mass of AgI forms in gram?

(b) Use Appendix B tofind ΔH°rxn. in kJ

(c) What is ΔTsoln (assume thevolumes are additive and the solution has the density and specific heat capacity of water)? in K

In: Chemistry

Dinitrogen pentoxide (N2O5) decomposes in chloroform as a solvent to yield NO2 and O2. The decomposition...

Dinitrogen pentoxide (N2O5) decomposes in chloroform as a solvent to yield NO2 and O2. The decomposition is first order with a rate constant at 45 oC of 1.0 x 10–5 s–1. Calculate the partial pressure (in atm) of O2 produced from 1.00 L of 0.600 M N2O5 solution at 45 oC over a period of 20.0 h if the gas is collected in a 10.0-L container. (assume that the products do not dissolve in chloroform.)

In: Chemistry

The combustion of acetylene C2H2 is a spontaneous reaction given by the equation: 2C2H2 (g) +...

The combustion of acetylene C2H2 is a spontaneous reaction given by the equation: 2C2H2 (g) + SO2(g) --> 4CO2 (g) + 2 H2O(l)

As expected for a combustion the a combustion the reaction is exothermic.

a.) What is the sign of Delta H?

b.) What do you expect for the sign of Delta S?

c.) Explain the spontaneity of the reaction in terms of the enthalpy and entropy changes.

Please show work and explain

In: Chemistry

Suppose you titrate 80.0 mL of 2.00 M NaOH with 20.0 mL of 4.00 M HCl....

Suppose you titrate 80.0 mL of 2.00 M NaOH with 20.0 mL of 4.00 M HCl. What is the final concentration of OH- ions.

In: Chemistry

In a study designed to prepare new gasoline-resistant coatings, a polymer chemist dissolves 6.077 g poly(vinyl...

In a study designed to prepare new gasoline-resistant coatings, a polymer chemist dissolves 6.077 g poly(vinyl alcohol) in enough water to make 100.0 mL of solution. At 25

In: Chemistry

Calculate the equivalence point potential for the titration of ferrous ion with dichromate ion in H2SO4

Calculate the equivalence point potential for the titration of ferrous ion with dichromate ion in H2SO4

In: Chemistry

Show the complete mechanism for the acid-catalyzed reaction of acetaldehyde with ethanol to form an acetal.

Show the complete mechanism for the acid-catalyzed reaction of acetaldehyde with ethanol to form an acetal.

In: Chemistry

Freezing point depression can be used to experimentally determine the van't Hoff factor of a solute...

Freezing point depression can be used to experimentally determine the van't Hoff factor of a solute in solution. Given the data in the table, please answer the questions below and determine the "real" van't Hoff factor of the solute.

Experimental Results

Mass of solvent (water) 5.267 g
Freezing point of water 0.00°C
Freezing point depression constant (Kf) of water 1.86°C/m
Mass of solution 6.121 g
Freezing point of solution -3.73°C

a. What mass of solute was used?

b. What is the freezing point depression, ΔTf, of the solution?

c. What is the colligative molality, mc, of the solution?

d. How many moles of solute particles are present in solution?

e. If the solute has a molar mass of 235.28, what is the van't Hoff factor, i, for the solute? (Remember that experimentally, i does not have to be an integer!)

In: Chemistry

Given the following solubilities in grams/100ml of water (these are the amounts that stay in solution...

Given the following solubilities in grams/100ml of water (these are the amounts that stay in solution at these temperatures):

caffeine 1.35g (16 degrees Celcius) 45.5g (65 degrees celcius)

NaCl 35.7g (0 degree celcius) 39.1g (100 degrees celcius)

Suppose that 20g of a mixture that is 75% caffeine and 25% NaCl is crystallized from 100mL of boiling water and cooled to 16 degrees celcius.

a) how much of the caffeine from this mixture stays in solution at 16 degrees celcius?

b) what is the most caffeine from this mixture that can be expected to cystallize?

c) How much NaCl from the original mixture stays in solution?

In: Chemistry

If you start with 3.0×10^10 I−131 atoms, how many are left after approximately 1month? I−131 has...

If you start with 3.0×10^10 I−131 atoms, how many are left after approximately 1month? I−131 has a half-life of 8.0 days. Express your answer using two significant figures.

In: Chemistry

An unidentified covalent molecular compound contains only carbon, hydrogen, and oxygen. When 7.40 mg of this...

An unidentified covalent molecular compound contains only carbon, hydrogen, and oxygen. When 7.40 mg of this compound is burned, 21.98 mg of CO2 and 3.00 mg of H2O are produced. The freezing point of camphor is lowered by 10.4

In: Chemistry

Draw an example of an octahedral complex that takes part in a ligand to metal charge...

Draw an example of an octahedral complex that takes part in a ligand to metal charge transfer.

In: Chemistry

I have a few questions relating to ph and whatnot.. 1) Calculate the pH of 0.0010...

I have a few questions relating to ph and whatnot..

1) Calculate the pH of 0.0010 M Ca(OH)2 solution. (to 2 decimal places)

2) Determine the pH of a KOH solution made by mixing 0.251 g KOH with enough water to make 1.00 � 102 mL of solution.

3) Calculate the pH of 0.0171 butanoic acid, Ka=1.52 x 10-5. Answer in 4 significant figures.

4) Calculate the pH of 0.00000M C5H5N solution. Kb=1.5 x 10-9. Answer in 3 decimal places.

5) Calculate the pKa of a 0.080M HOCl solution with a pH of 3.22.

6) A solution containing NH3(aq) and NH4Cl(aq) has a pH of 9.5. What is the [NH3]/[NH4+] ratio in this solution? For ammonia, Kb = 1.8 � 10�5.

In: Chemistry