(a) ammonia (NH3) and cyclohexanone (b) H+ and ethanol (c) azide (N3-) and bromoethane (d) nitrogen (N2) and propane (e) triethylamine and H+, Draw the electron arrow pushing mechanism of the potential interaction in problem 34. (d) ScCl3 is a Lewis acid. Also, give its IUPAC name. To calculate the new k value use the following k2/k1=Ae-(Ea/RT2)/Ae-(Ea/RT1) and the constant, A, cancels. Carboxylic acids are characterized as weak acids, meaning that they do not fully dissociate to produce H + cations in a neutral aqueous solution.
This makes these nonpolar amino acids to have a neutral charge. Looking at the structure of an amino acid (as a zwitterion), it seems that the part of the molecule with the amino group and the carboxylic acid group are quite polar (the amino group has a positive hydrogen and the carboxylic acid group has a negative oxygen). In problem 28 use electron pushing arrows to show what is occurring, looking from left to right. The lowest energy conformation would be (d) anti staggered, where the larger CH3 groups are anti and there is no eclipsed group. In each of the following equations label the Brønsted acid and base, on both sides. However, the entropy does increase and so the free energy decreases. Dimers: pairs of molecules connected by two hydrogen bonds. (d) It is likely that the reaction involves one reactant and yields two products. The higher the molecular weight the higher the boiling point, but also the more branched a molecule is the lower the boiling point. (b) One of these reactions as a ∆So <0 (-35 cal mol-1) and the other has a ∆So=0. (b) Reaction (i) involves the combination of two molecules into one. It is in a positive oxidation state hand has three electronegative halogens attached, and so the scandium center is an electron acceptor. (b) (i) H2O=Weaker Base HCN=Weaker Acid; H3O+=Stronger Acid CN-=Stronger Base. Explain why. 2,3,4-trimethylpentane<2,3-dimethylhexane<3-methylheptane
(b) The hydride anion is negatively charged, and it is nucleophilic. A tray of ice cubes is left out on the counter in a room, and the ice cubes melt. This is based off of the 1 position in the alkyl group, connected to the dashed bond. Watch the recordings here on Youtube!
Using ΔG=ΔH-TΔS, where ΔH=-1000 cal/mol and ΔS=-2cal/mol at T=200K, which of the following is true. For each of the following molecules denote the bond polarities, δ+ or δ-. (a) AlCl3 (b) H2O (c) ZnCl2 (d) ScCl3 (e) N3- (f) CH3CH2O-. (c) ZnCl2 is a Lewis acid.
Write the rate law for each reaction, and similar to in problem 35 draw the structures with any electrostatic interactions. Are the reactions favorable at these temperatures? If the room is a closed system, what is the total enthalpy of the system (room + ice)? Identify the functional groups in each compound. How would the temperature of the ice, now water, and the room compare? Which of the following is true about 2,3-dimethylbutane? Identify whether each species is nucleophilic or electrophilic, (a) Fluoride anion, F- (b) Hydride anion, H- (c) acid chloride, CH3COCl (d) ScCl3 (e) N,N'-diethylcarbodiimide. Carboxylic acids are polar molecules; they tend to be soluble in water, but as the alkyl chain gets longer, their solubility decreases due to the increasing hydrophobic nature of the carbon chain. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. The equilbrium constant for the reaction as drawn, left to right, is very small. Have questions or comments? (c), aldehyde is not in the molecule. The azide has an overall negative charge, and a Coulombic attraction is present. Although the bond arrangement around the C atom in CH2Cl2 is symmetrical, the differing polarities of the C–H and C–Cl bonds means the effect of the polar bonds is not cancelled, so the molecule is polar. For more information contact us at email@example.com or check out our status page at https://status.libretexts.org. If not, in what ways? Legal. The important thing here is the polarization of the C-Br bond, making the carbon electrophilic. Molecule (a) does not contain a tertiary carbon, it is only bonded to two other carbon atoms. (iii) Ka H3O+= [H+][H2O]/[H3O+]= 101.7 and Ka HCN= [CN-][H+]/[HCN]= 10-9.2 and the Keq= Ka HCN/Ka H3O+ = 10-9.2/101.7 = 1.26x10-11 , the case is the same as the previous problem. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. ΔGo=-(1.986)(273+25)ln(85/15)= -1027 cal or -1.027 kcal. (a) 10 kcal mol-1 (b) 25 kcal mol-1 (c) 50 kcal mol-1. (a) 2,3,4-trimethylhexane (b) nonane (c) 2,3-dimethylpentane (d) 3-methylheptane. These are homework exercises to accompany Chapter 2 of Vollhardt and Schore's "Organic Chemistry" Textmap. It is an electron donor. This makes sense because the favors the left, so calculating the equilibrium to the right would mean a very small equilibrium constant. ∆Go= -36 - 303.15(-35x10-3) = -25 kcal mol-1 Favorable, ∆Go= -36 - 1073.15(-35x10-3) = +1 kcal mol-1 Not Favorable, ∆Go= -24 - 303.15(0) = -24 kcal mol-1 Favorable, ∆Go= -24 - 1073.15(0) = -24 kcal mol-1 Favorable, (a) (i) H2O=Weaker Base HF= Weaker Acid; H3O+= Stronger Acid F-=Stronger Base, (ii) From above, the equilibrium would lie to the left, (iii) Using the pKa we can find the Ka for each acid, Ka=10-pKa HF Ka=10-3.45 and H3O+ Ka= 101.7. for simplicity, only one resonance structure was shown as the Lewis acid/base adduct. Make sure not to draw a pentavalent carbon in (a) (use the oxygen atom) and (b) (substitute the bromine and have it leave). The Arrhenius equation is k=Ae-(Ea/RT) where A is a constant.
Also draw the Newman projection of each. (c) Acid chlorides are similar to esters and ketones in that there is an electrophilic carbon double bonded to the oxygen, but acid chlorides are typically much more reactive. (c) - gauche staggered is the conformation.