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pKa Solutions Library

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51 solutions

pKa

Q. Estimate the pKa values for the functional classes represented by the given molecules. 

Solved • Mar 16, 2020

pKa

Q. Which of the following is the strongest acid? a. CH3OH b. CH3OH2+ c. CH3NH2 d. CH3NH3+ e. H2N-

Solved • Apr 17, 2019

pKa

Q. Which of the following is the strongest base?a. HOMgBrb. H2Oc. CH4d. CH3OHe. CH3MgBr

Solved • Apr 9, 2019

pKa

Q. The Pka of methanol (CH3OH) is 15.5 and the Pka of ammonia (NH 3) is 36. Which is a stronger base CH3O- or NH2-? Briefly explain your answer.

Solved • Apr 9, 2019

pKa

Q. Rank the following in order of basicity. (1 – least basic, 3 – most basic)

Solved • Jun 12, 2017

pKa

Q. Order the following molecules by increasing pKa values: CH2 = CH2 (1), HOEt (2), H2SO4 (3), CH3CH2CH2CH2CO2H (4). ___ < ___ < ___ < ___ ...

Solved • Jun 9, 2017

pKa

Q. Circle the weakest acid:  

Solved • May 31, 2017

pKa

Q. Considering only the most acidic proton in each molecule ( bold), rank in order of increasing acidity. (1 = least acidic, highest pka; 5 = most aci...

Solved • May 5, 2017

pKa

Q. Rank order all of the following with respect to relative acidity. The acidic H atom in question is indicated with the arrow for each molecule. On t...

Solved • Jan 3, 2017

pKa

Q. Fill in the appropriate pKa values below. Remember that certain factors will affect these general pKa values.

Solved • Nov 14, 2016

pKa

Q. Circle the most acidic proton in each of the following molecules.

Solved • Sep 16, 2016

pKa

Q. Predict the pKa for the following molecules:

Solved • Aug 22, 2016

pKa

Q. Rank the acidity of the labeled protons in the following molecule from lowest to highest acidity.   

Solved • Aug 15, 2016

pKa

Q. Circle the weakest base.

Solved • Aug 5, 2016

pKa

Q. The free-energy change, ΔG°, for the ionization of acid HA is 21 kJ mol-1 ; for acid HB it is -21 kJ mol-1 . Which is the stronger acid?  

Solved • Jun 15, 2016

pKa

Q. Arrange the following in order of increasing basicity: (c) CH3CH=CH-, CH3CH2CH2-, CH3≡C-

Solved • Jun 15, 2016

pKa

Q. Arrange the following in order of increasing basicity: (b) CH3O-, CH3NH-, CH3CH2-

Solved • Jun 15, 2016

pKa

Q. Arrange the following in order of increasing basicity: (a) CH3NH2, CH3NH3+, CH3NH-  

Solved • Jun 15, 2016

pKa

Q. Arrange the following compounds in order of decreasing acidity:  

Solved • Jun 15, 2016

pKa

Q. Arrange the following compounds in order of decreasing acidity: (a) CH3CH=CH2, CH3CH2CH3, CH3C≡CH

Solved • Jun 15, 2016

pKa

Q. (b) Arrange the conjugate bases of the acids given in part

Solved • Jun 15, 2016

pKa

Q. (a) Arrange the following compounds in order of decreasing acidity and explain your answer: CH3CH2NH2, CH3CH2OH, and CH3CH2CH3.

Solved • Jun 15, 2016

pKa

Q. Acid HA has pKa = 20; acid HB has pKa = 10. (a) Which is the stronger acid?

Solved • Jun 15, 2016

pKa

Q. List the acids you gave as answers to Exercise 3.20 in order of decreasing acidity.

Solved • Jun 15, 2016

pKa

Q. List the bases you gave as answers to Exercise 3.18 in order of decreasing basicity.

Solved • Jun 15, 2016

pKa

Q. Rank the following in order of decreasing basicity. As in the preceding problem, Table 1.8 should prove helpful. 

Solved • Jun 13, 2016

pKa

Q. Rank the following in order of decreasing acidity. Although none of these specific structures appear in Table 1.8, you can use analogous structures...

Solved • Jun 13, 2016

pKa

Q. The structure of montelukast, an antiasthma drug, is shown here.  (b) Use Table 1.8 to identify the most acidic and most basic sites in the molecu...

Solved • Jun 13, 2016

pKa

Q. Asteltoxin, isolated from the cultures of Aspergillus stellatus, exhibits a potent inhibitory effect on the activity of E. coli BF1-ATPase. During ...

Solved • May 24, 2016

pKa

Q. Consider the following compound with molecular formula  C 4H8O: (b) Draw a constitutional isomer that you expect will be less acidic than the comp...

Solved • May 24, 2016

pKa

Q. Consider the following compound with molecular formula  C 4H8O: (a) Draw a constitutional isomer that you expect will be  approximately one trilli...

Solved • May 24, 2016

pKa

Q. For each compound below, identify the most acidic proton in the compound: 

Solved • May 23, 2016

pKa

Q. For each compound below, identify the most acidic proton in the compound: 

Solved • May 23, 2016

pKa

Q. For each pair of compounds below, identify the more acidic compound:

Solved • May 23, 2016

pKa

Q. For each pair of compounds below, identify the more acidic compound:

Solved • May 23, 2016

pKa

Q. For each pair of compounds below, identify the more acidic compound:

Solved • May 23, 2016

pKa

Q. For each pair of compounds below, identify the more acidic compound:

Solved • May 23, 2016

pKa

Q. For each pair of compounds below, identify the more acidic compound:

Solved • May 23, 2016

pKa

Q. In each group of compounds below, select the most acidic compound:

Solved • May 23, 2016

pKa

Q. In each group of compounds below, select the most  acidic compound:

Solved • May 23, 2016

pKa

Q. Which is the order from the most acidic to least acidic? (A) III > IV > II > I (B) II > UV > I > III (C) II > III > IV &gt...

Solved • May 6, 2016

pKa

Q. Rank the following from least to most acidic.

Solved • May 2, 2016

pKa

Q. Which proton in this compound would be most acidic? A) A B) B C) C D) D

Solved • Apr 23, 2016

pKa

Q. What is the order of acidity of the indicated hydrogen atoms in this molecule? Rank from most acidic to least acidic? a) b > a > c b) c &gt...

Solved • Apr 23, 2016

pKa

Q. Which statement regarding the two amino acids (phenylalanine & tryptophan) below is true? A) tryptophan is a stronger acid than phenylalanine ...

Solved • Mar 17, 2016

pKa

Q. Identify the strongest Bronsted acid:  

Solved • Mar 17, 2016

pKa

Q. Order the following in increasing order of acidity. Hl, Acetic Acid, Ethanol, and Octane. 

Solved • Feb 22, 2016

pKa

Q. Which one has the lowest pKa? a) HO b) H2O c) H3O+

Solved • Feb 8, 2016

pKa

Q. ​​Circle the least acidic proton in the following compound and explain your answer.  

Solved • Jan 28, 2016

pKa

Q. Which of the following would represent the strongest acid?a. pKa = 10.5b. Ka = 2.5 x 10 ­-5c. Ka = 2.5 x 10 -6d. pKa = 4.90

Solved • Jan 28, 2016

pKa

Q. Rank the acidity of the labeled protons in the following molecule from the most acidic to least acidic:   a. Hb > Ha > Hc b. Ha > Hb &g...

Solved • Jan 28, 2016