Portmess Homework Q&S 75

Portmess Homework Q&S 75 - 69 ALCOHOLS AND ALKYL...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
4.7 Since the p K a of HCN is given as 9.1, its K a 5 10 2 9.1 . In more conventional notation, K a 5 8 3 10 2 10 . Hydrogen cyanide is a weak acid. 4.8 Hydrogen cyanide is a weak acid, but it is a stronger acid than water (p K a 5 15.7). Since HCN is a stronger acid than water, its conjugate base (CN 2 ) is a weaker base than hydroxide (HO 2 ), which is the conjugate base of water. 4.9 An unshared electron pair on oxygen abstracts the proton from hydrogen chloride. 4.10 In any proton-transfer process, the position of equilibrium favors formation of the weaker acid and the weaker base from the stronger acid and base. Alkyloxonium ions (ROH 2 1 ) have approximately the same acidity as hydronium ion (H 3 O 1 ,p K a 52 1.7). Thus hydrogen chloride (p K a ø 2 7) is the stronger acid. tert -Butyl alcohol is the stronger base because it is the conjugate of the weaker acid ( tert -butyloxonium ion). The equilibrium constant for proton transfer from hydrogen chloride to tert -butyl alcohol is much greater than 1.
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 09/20/2011 for the course CHM 2210 taught by Professor Reynolds during the Spring '01 term at University of Florida.

Ask a homework question - tutors are online