Ace - AI Tutor
Ask Our Educators
Textbooks
My Library
Flashcards
Scribe - AI Notes
Notes & Exams
Download App
Michelle O mahony

Michelle O.

Divider

Questions asked

INSTANT ANSWER

(ii) When the product of the reaction of enantiomerically pure (S)-2-octyl tosylate (1) with \( \mathrm{Na}_{2}\left[\mathrm{Fe}(\mathrm{CO})_{4}\right] \) is treated first with carbon monoxide (CO) and then with methyl iodide (MeI), the organic product is (R)-3-methyl-2-nonanone (2) in a \( 99 \% \) enantiomeric excess. (1) (2) (a) Draw structures of the organometallic intermediates along the reaction pathway. [2 marks] (b) Label the reaction type of each individual reaction step and show the oxidation state, \( \mathrm{d}^{\mathrm{n}} \) electron count and whether the 18 electron rule is being obeyed for any metal compounds. [2 marks] (c) What is the mechanistic implication of this overall transformation for the first step of the reaction sequence? [1 mark]

View Answer
divider
INSTANT ANSWER

(QUESTION 2 continued) (ii) The active form of the catalyst used for the catalytic enantiospecific hydrogenation of \( \alpha \)-acetamido cinnamic esters (see below for formula of ester) is given below which has two solvent molecules on the metal centre. (a) Show how the active catalyst is prepared, (b) State what solvent is used in the catalytic cycle, (c) Sketch how the catalyst coordinates to following the \( \alpha \)-acetamido cinnamic ester. \( \mathrm{CH}_{3} \mathrm{C}(\mathrm{O}) \mathrm{NHCH}\left(\mathrm{COOCH}_{3}\right) \mathrm{CHPh} \)

View Answer
divider
INSTANT ANSWER

QUESTION 2 (i) For the following metal/ligand combinations \( \mathbf{A}-\mathbf{C} \) : (a) Sketch out a neutral structure (using the number of electrons specified), (b) Show your electron counting, (c) Comment on the likely stability of each complex, (d) Indicate the charge on each ligand, (e) Show the oxidation state of the metal, (f) Give the \( \mathrm{d}^{\mathrm{n}} \) electron count of the metal, Bear in mind the following guidelines: 1) Do NOT use abbreviations in your sketches. 2) Use at least one of each metal and ligand listed. 3) Try to keep your structure as simple as possible (bimetallic complexes are acceptable, nothing higher in terms of number of metal centres). A Yb, \( \eta^{5}-\left(1,3-{ }^{-} \mathrm{Bu}_{2} \mathrm{C}_{5} \mathrm{H}_{3}\right), \mathrm{EtOCH}_{2} \mathrm{CH}_{2} \mathrm{OEt} \), iso-butyl (18e) B \( \mathrm{Os} \), Cyclohexene, \( \mathrm{MePCH}_{2} \mathrm{PMe} \), pyridine, \( \mathrm{CO}, \mathrm{Cl} \) (17e) C Mo, butadiene, D, 2-methyl-but-3-yne, \( \mu_{2}-\mathrm{AsBu}^{\mathrm{i}}{ }_{2} \) (16e) [9 marks]

View Answer
divider
INSTANT ANSWER

The hydroxyl radical is found in the atmosphere in very low abundance, approximately 10' molecules per cm'. Copper is a face-centred cubic metal having a lattice parameter of 361 pm. Assuming a sticking coefficient of 0.5, calculate how long it takes for a monolayer to form on a 1 cm? copper surface (100) exposed to hydroxyl radicals under atmospheric conditions (P = 1 atm, T = 25 °C

View Answer
divider
INSTANT ANSWER

(ii) The data in the table below are for chemisorption of hydrogen on copper powder at a temperature of \( 25^{\circ} \mathrm{C} \). Graphically determine if the data can be fitted to a Langmuir isotherm. Find the value of \( K \) for the adsorption equilibrium and the adsorption volume corresponding to complete coverage. \begin{tabular}{|c|c|c|c|c|c|} \hline \begin{tabular}{c} \( \boldsymbol{p} \) \\ \( (\mathbf{m m} \mathbf{~ H g}) \) \end{tabular} & 0.19 & 1.90 & 4.05 & 7.50 & 11.95 \\ \hline \begin{tabular}{c} \( \boldsymbol{V}_{a} \) \\ \( \left(\mathrm{~cm}^{-3}\right) \) \end{tabular} & 0.042 & 0.221 & 0.321 & 0.411 & 0.471 \\ \hline \end{tabular} [8 marks]

View Answer
divider
ANSWERED

Anand Jangid verified

Numerade educator

Calculate the number of atoms per unit area of the (100) surface of tungsten (W), which has a bcc unit cell and a lattice constant of 316 pm. Calculate the surface area of W that adsorbs 103 cm' (at 1.013 bar and 0 °C) of nitrogen (Nz) per gram of W to form a monolayer.

View Answer
divider
ANSWERED

George Bennett verified

Numerade educator

Sketch the energy levels found using Hückel theory for butadiene and for cyclobutadiene. Using these Hückel theory results, which of these molecules do you propose to be stable and explain your reasoning (do not use the Hückel rule in your answer).

View Answer
divider
INSTANT ANSWER

Denoting the matrix elements by a and write out a Hückel matrix for (a) benzene and (b) 1,3,5,7-octatetraene. Describe the chemical meaning of the entries a and B. Extended Hückel theory removes some approximations found in Hückel theory. Write out the expressions for a and B using extended Hückel theory.

View Answer
divider
INSTANT ANSWER

Explain how the variational principle is used to assess the quality of a trial wavefunction. In a calculation on the B atom, the following trial wavefunctions were used: (a): 1s 2s 2p 3s 3p 3d, (b) 1s 2s 2p, (c) 1s 2s 2p 3s and (d) 1s 2s 2p 3s 3p. Sketch the relative energies of these wavefunctions compared to the true energy and explain your reasoning for this ordering

View Answer
divider