Pick a number between 100 and 1000. For that energy in kJ/mol, what are the associated wavelength (nm), frequency (1/s = Hz) and wavenumber (cm-1)?

Draw a detailed diagram of the TLC process

Hydrogen gas is used as a fuel instead of fossil fuels. Storage of hydrogen is a challenge. One avenue of research involves chemical storage such as incorporating hydrogen as part of a metal hydride. In the following reaction sodium borohydride, NaBH4, is used as a means for storing and later generating the hydrogen gas in situ where it is needed as a fuel. Application of heat and use of a catalyst drives the reaction forward. NaBH4(s) + 2 H2O(l) → NaBO2(s) + 4 H2(g) To test the efficiency of the reaction, 0.11 g of sodium borohydride is catalytically decomposed and 244 mL of hydrogen gas is collected over water at 30.0 °C under an atmospheric pressure of 752 mmHg. Calculate the % yield of the reaction

The following reaction is first order in N2O5:
N2O5(g)?NO3(g)+NO2(g)

The rate constant for the reaction at a certain temperature is 0.053/s.

A)

Calculate the rate of the reaction when [N2O5]= 5.4

which of the following is a process with a negative S?

A solution of a specific vitamin has λmax = 287 nm and a concentration of 8.76 × 10-7 M. The absorbance of the solution at 287 nm is A = 0.190. What is the molar absorptivity of the vitamin at 287 nm? (sample pathlength = 1.00 cm)

pls answer 1-4 I would like to check with my answer

1) Saponification of triglycerides gives glycerol and fatty acid salts as shown in the equation below. The groups R1, R2 and R3 represent hydrocarbon chains that may be the same or different.

Saponification is actually a hydrolysis reaction. Explain what a hydrolysis reaction is and the role of sodium hydroxide in this process.

2)The over-the-counter drug Ibuprofen is a 1:1 mixture of R and S isomers of the compound 2-(4-isobutylphenyl)propanoic acid. The two compounds have identical physical properties, but only the S isomer has drug activity. Explain the structural difference between these isomers that accounts for these observations.

3) Halogenation of alkanes in the presence of light is an example of an organic reaction that occurs via free radical intermediates.One example of this is the reaction between methane and chlorine shown in the equations below. Free radical reactions occur in a series of steps called Initiation, Propagation and Termination. Write equations to show an example of each of these steps in the reaction of methane with chlorine in the presence of light.

Initiation reaction (1 mark)

Propagation reaction (1 mark)

Termination reaction (1 mark)

4) The preparation of ethoxybenzene from the reaction between sodium phenoxide and bromoethane is shown in the equation below. Like most organic reactions, this can be described as an interaction between an electron rich species (nucleophile) and an electron deficient species (electrophile).

a) Examine the equation and clearly label each reactant as the nucleophile or electrophile as appropriate.

b) Write an equation to show how sodium phenoxide could be prepared from phenol (hydroxybenzene).

Describe the characteristic chemical step that occurs during covalent catalysis. Which four different types of catalytic mechanisms did we discuss to hydrolyze peptide bonds in proteins?

Write the balanced net ionic equation for the reaction that occurs in the following case: Cr2(SO4)3(aq)+(NH4)2CO3(aq)→ Part b. Identify the spectator ions in this reaction

9) for the reaction
[ 2Al + 3H2SO4 → Al2(SO4)3 + 3 H2SO4] 6.0 g of Al (MW=26.98 g/mol) are added to 12.0 mL of 0.20 M of H2SO4

A) what is the limiting reagent in the above reaction?

b) how many miles of H2SO4 will be formed?

c) how many grams of Al2(SO4)3 (MW=342.15 g/mol) are produced in the reaction?

Consider a buffer made by adding 132.8 g of NaC₇H₅O₂ to 300.0 mL of 2.15 M HC₇H₅O₂ (Ka = 6.3 x 10⁻⁵) What is the pH of the buffer after 0.750 mol of H⁺ have been added?

Methanol is prepared industrially from synthesis gas (CO and H2). CO(g) + 2H2(g) ⇌ CH3OH(g); ΔH° = -21.7 kcal Would the fraction of methanol obtained at equilibrium be increased by raising the temperature? Explain.

5a. When 4.355 grams of a hydrocarbon, C_xH_y, were burned in a combustion analysis apparatus, 14.72 grams of CO₂ and 3.014 grams of H₂O were produced.

In a separate experiment, the molar mass of the compound was found to be 26.04 g/mol. Determine the empirical formula and the molecular formula of the hydrocarbon.

• Enter the elements in the order presented in the question.
  

  empirical formula =

  molecular formula =

5b.
A 12.57 gram sample of an organic compound containing C, H and O is analyzed by combustion analysis and 17.83 grams of CO₂ and 10.95 grams of H₂O are produced.

In a separate experiment, the molar mass is found to be 62.07 g/mol. Determine the empirical formula and the molecular formula of the organic compound.

• Enter the elements in the order C, H, O
  

  empirical formula =

  molecular formula =

5c.

A 4.550 gram sample of an organic compound containing C, H and O is analyzed by combustion analysis and 6.452 grams of CO₂ and 3.963 grams of H₂O are produced.

In a separate experiment, the molar mass is found to be 62.07 g/mol. Determine the empirical formula and the molecular formula of the organic compound.

• Enter the elements in the order C, H, O
  

  empirical formula =

  molecular formula =

Describe the principle of separation in a column used for size – exclusion chromatography. What is the separation range in term of molecular weight? Give the definition of “gel filtration: and “gel permeation”.