Posted by A.A on .
NH3 and CH3NH2 have Kb values of 1.8 x 10-5 and 5.0 x 10-4, respectively; which of the following statement(s) is (are) CORRECT?
(i) CH3NH2 is a stronger base than NH3.
(ii) the conjugate acid of CH3NH2 is a stronger acid than the conjugate acid of NH3.
(iii) 0.1 M aqueous solutions of CH3NH2 and NH3 have the same concentration of hydroxide ion, OH-.
i know i is true, but am not sure of the others
OK. If you know (i) is true (you're right), then you KNOW (III) can't possibly be right. Right? Because if CH3NH2 is a stronger base than NH3, then CH3NH2 must give a higher concn of OH^- than NH3. Now what about (ii)?
If CH3NH2 is a stronger base than NH3, then the conjugate acid of CH3NH2 must be weaker than the conjugate acid of NH3. By knowing (i) is right, you should be able to reason about the other two.
What is the H+ ion concentration of this solution?
A solution is made by dissolving 0.0112 g KOH in enough water to make 1.0 liter of solution. What is the H+ ion concentration of this solution?
a. ) 2.0 x 10-3 M
b. ) 8.0 x 10-2 M
c. ) 1.2 x 10-13 M
d. ) 5.0 x 10-11 M
e. ) 5.0 x 10-12 M