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For the endothermic reaction

Le Chtelier's principle predicts that __________ will result in an increase in the number of moles of at equilibrium.

1. Increasing the temperature
2. Decreasing the temperature
3. Increasing the pressure
4. Removing some of the
5. Adding more

Consider the endothermic reaction:
Fe3 ( aq)+Cl- (aq )_ FeCl2+( aq)
Use Le Chatelier’s principle to predict how the equilibrium concentration of the complex ion 
 will change when: 
i) Fe(NO3 ) 3is added [2]

Why is fixing the smear important?

Calculate the heat of reaction using the average bond dissociation energies given in the introduction 

CH4 + 2O2 → CO2 + 2H2O

For the reaction N2O4(g)⇌2NO2(g), the equilibrium concentrations at 25∘C are [NO2]=0.0325mol/L and [N2O4]=0.147mol/L

1)What is the value of K at 25∘C?

K=?

For the reaction

the rate law can be written as:

where is the rate constant for the reaction.

Under the condition , a good linear regression fit can be obtained for a plot of versus . For two sets of different initial concentrations, the equations of were found to be:

Equation of regression line

What is the value of ? 

What is the value of ?

What is the rate constant (with consistent units)?

Ammonium nitrate () is common nitrogen fertilizer and might be used in landscaping around the pond. You add this to the sample and observe that acetic acid, ethanol, and lactic acid are rapidly consumed, and and are produced. Based on these data, which of the following statements are true? (more than one could be correct)

a. Some organisms are capable of respiration.

b. The produced is likely a byproduct of organisms using the citric acid cycle

c. Some of the prokaryotes that can use ammonia () are terminal electron acceptors.

d. Some prokaryotes can use nitrate () as a terminal electron acceptor.

e. Some of the prokaryotes can convert nitrate () to and , and are using as their terminal electron acceptor.

Calculate the maximum tensile force that a polypeptide chain can withstand, assuming that the covalent bonds which hold the backbone together can be described by the Lennard-Jones potential function:

in which the values of  and  for carbon-carbon bonds are respectively and , while the corresponding values for carbon-nitrogen nitrogen bonds are respectively and .

For the formation of a photchromic imine you use ammonium bromide. Give 2 reasons why you cannot use concentrated HBr.

Florokarbon, Cı- ₂ Cı ₃ F ₃ 47.6 kadar bir normal kaynama noktasına sahip ^o Cı spesifik ısısı C'de ₂ Cı ₃ F ₃ (I) ve Cı- ₂ Cı ₃ F ₃ (g) 0.91 J / g'dır. ^O ° C ve 0.67 J / g. ^o C, sırasıyla. Bileşiğin ΔHvap'ın buharlaşma ısısı 27.49 kJ / mol'dür. 5.0 sıvı bu bileşiğin 50.0 gramını dönüştürülmesi için (kj olarak) entalpi değişimi hesaplamak ^o 80.0 gaza C ^O C (Mw.of Cı ₂ Cı ₃ F ₃ = 187,37 g / Mol)

How does the electrical conductivity of ionic solids and solutions compare to the electrical conductivity of molecular solids and solutions? 

The vapor pressure of liquid ethyl amine, , is at . A sample of is placed in a closed, evacuated container of constant volume at a temperature of . It is found that all of the is in the vapor phase and that the pressure is . If the temperature in the container is reduced to , which of the following statements is correct?

1. Liquid ethyl amine will be present.
2. The pressure in the container will be .
3. No condensation will occur.
4. Only ethyl amine vapor will be present.
5. Some of the vapor initially present will condense.

Which of the following is TRUE about protein conformation.

A. Some proteins are globular, some are fibrous.
B. In globular proteins, hydrophobic parts of amino acid residues tend to occur in the interior of the folded, globular protein.
C. In keratin, disulfide bridges or bonds occur between keratin chains, increasing the strength of the structure formed by keratin.
D. H bonding occurs between amino acid backbone atoms and also between some side chains in the folded globular state.
E. All of the above is true.

A solution prepared by mixing of and of was titrated with in a cell containing a silver indicator electrode and a reference electrode of constant potential . The reference electrode is attached to the positive terminal of the potentiometer, and the silver electrode is attached to the negative terminal. The solubility constant of is and the solubility constant of is .

(a) Which precipitate forms first?

(b) What is the cell potential when the following volumes of have been added? , , , , , , and .

We have seen (Equation (2.3.5)) that, for any system,

For the van der Waals gas the energy , in which (Equation (2.2.15)).

Use these two expressions and the van der Waals equation to obtain an explicit expression for the difference between and for a van der Waals gas.

• In both words and in terms of a mathematical equation, describe the relationship between pH and the ratio of base concentration to the acid concentration that you observed in this data.

• Compare the addition of a strong acid to water to the addition of a strong acid to your buffer.  Suggest a reason for any difference you observed.

• Describe the effect of diluting the acid.  Upon sufficient dilution, what would you predict your final pH to be?

• Describe the effect of diluting the base.  Upon sufficient dilution, what would you predict your final pH to be?

• Compare the pH values for your most diluted buffered sample to the undiluted sample.  Do the same for your acid and base samples.  

A mixture having a volume of and containing and was titrated with .

;

;  

The after adding of solution is

Thioamide drugs can be determined quantitatively by cathodic stripping analysis. Deposition occurs at versus the . During the stripping step, the potential is scanned cathodically, and a stripping peak is observed at . In a typical application, a sample of urine was mixed with of a pH buffer. Following a deposition, a peak current of  was measured. A addition of a solution of the thioamide drug was added to the same solution. A peak current of was recorded following the same deposition time. Report the drug’s molar concentration in the urine sample.

Automotive airbags inflate when sodium azide decomposes explosively to its constituent elements:

 

How many moles of are produced by the decomposition of of sodium azide?

A stream of air at and contains water by volume. Calculate:

a) The percentage of the vapour that condenses and the final composition of the gas phase if the air is cooled to at constant pressure.

b) The percentage of the vapour that condenses and the final composition of the gas phase if, instead of being cooled, the air is compressed isothermally to .

You are attempting to determine by measuring the reaction velocity at different substrate concentrations, but you do not realize that the substrate tends to precipitate under the experimental conditions you have chosen. How would this affect your measurement of ?

Why does benzene have a higher HOMO LUMO gap that phenoxide?

Amino acid analysis of an octapeptide revealed the following composition:

2 Arg 1 Gly 1 Met 1 Trp 1 Tyr 1 Phe 1 Lys

The following facts were observed:

a. Edman degradation gave

b. CNBr treatment yielded a pentapeptide and a tripeptide containing phenylalanine.

c. Chymotrypsin treatment yielded a tetrapeptide containing a C-terminal Trp, and two dipeptides.

d. Trypsin treatment yielded a tetrapeptide, a dipeptide, and free Lys and Phe.

e. Clostripain yielded a pentapeptide, a dipeptide, and free Phe.

What is the amino acid sequence of this octapeptide?

Calculate the degree of unsaturation in each of the following formulas: (a) Cholesterol, C27H46O

(c) Prostaglandin E1, C20H34O5

(e) Cortisone, C21H28O5

(b) DDT, C14H9Cl5

(d) Caffeine,C9H10N4O2

(f) Atropine, C17H23NO3

Dye molecules are of commercial importance because they are very intensely colored. Most dye molecules possess many multiple bonds and are often aromatic. Why is this type of structure important to the properties of the dye molecule?

Why would the isolation of pure amino acid be extremely difficult?

Write the chemical formulas of the major species present at equilibrium. 

Write the chemical formulas of the species and indicate which will act as an acid, base, or that will act as neither acids nor bases.

1.) 0.1 mol of KOH is added to 1.0 L of a 0.4 M HF solution.

2.) 0.02 mol of NaOH is added to 1.0 L of a solution that is 0.3 M in both HF and KF

What is the type of reaction for this chemical equation? Ag2S - Ag + S8

The hybridization of the carbon atom in the cation CH3+ is?

with explaining !

Commercially available concentrated hydrochloric acid is 37.0% w/w Hcl.its density is 1.18g/ml.using this information calculate the molarity of concentrated Hcl and the mass and volume (in ml) of solution containing 0.315 moles of Hcl.

If an access of aluminum metal is placed in the copper II chloride solution the aluminum will replace the copper causing the copper to come out of the solution as a solid if 1.9 g of copper (II) chloride reacted how many grams of copper metal be recovered from the solution

calculte and explain equations by dimensional analysis method 

Prepare standard solutions

You are required to prepare working standard solutions of 1.00 x 10-5,2.00 x 105,5.00 x 10, and 1.00 x 10 M glucose from a 0.100 M stock solution. You have available 100-mL volumetric flasks and pipets of 1.00-, 2.00-, 5.00-, and 10.00-mL volume. Outline procedure for preparing the working standards.

state the equation of line .ensure your values are to the correct number of significant figure .

a.  Which of the following will  react more strongly with CO?    Fe, Fe+2 or Fe=3
b.  Which of the following will  react more strongly with Ag+?    NH3    or PH3

The analysis of a compound shows that it's made up of 9.57% O, 6.66% H, 8.38%N and the rest is carbon

A solution was prepared by dissolving about of in approximately of water and standardizing against aliquots of . An average titration of was required. Calculate the molar concentration of the EDTA.