A few chemistry

I got the rest of the homework, but these are confusing me so much...ugghhhh.

1. The pH of a .400 M solution of iodic acid, HlO3, is .726 at 25 degrees C. What is the Ka(acid constant) at this temperature?

2. The pH of a .150 M solution of HClO is found to be 4.55 at 25 degrees C. What is KAfor HClO at this temp?

3. CH3CH2CH2NH2 is a weak base. At equilibrium, .039 M solution of it has an OH- concentration of 3.74 x 10^-3 M. What is the pH of this solution and Kb(base constant) for this this weak base?

HIO3 ==> H^+ + IO3^-

pH = 0.726. Use pH = -log(H^+) to calculate (H^+).
Then set up Ka expression.
(H^+) = (IO3^-) and (HIO3) = 0.4-(H^+).
Plug into Ka expression and solve for Ka.

2. Same process for #2.

3. Same process but this is Kb instead of Ka.
Post your work if you get stuck or want to check your answers.

Ok, so on #1, I did the antilog, and got 5.32, so I plugged it in.
HIO3=.4-5.32, =-4.92

But now I don't get what to do...

No, No. How in the world did you get 5.32?
pH = -log(H^+)
0.726 = -log(H^+)
-0.726 = log(H^+)
antilog -0.726 = (H^+) = 0.1879
Do this on your calculator.
Punch in 0.726, change sign to - (or punch in -0.726 initially) and punch the button that says 10x. That should give you 0.1879.
Let me know if you still are confused.

Woops, that wasn't what I was confused about. That was just my stupidity, forgetting to change the sign, first. I just don't really know where to go after I have all of these things plugged in and such..

Ka = (H^+)(IO3^-)/(HIO3)
Ka = (0.1879)(0.1879)/(0.4-0.1879) = ??

Ka = 0.166

  1. 👍 0
  2. 👎 0
  3. 👁 188
asked by Trish
  1. 2. The pH of a .150 M solution of HClO is found to be 4.55 at 25 degrees C. What is KA for HClO at this temp?
    The answer is Ka=5.0*10^-9

    1. 👍 0
    2. 👎 0
    posted by Ryann
  2. why did you subtract .1879 from .4? on this part:
    Ka = (0.1879)(0.1879)/(0.4-0.1879) = ??

    1. 👍 0
    2. 👎 0
    posted by theresa

Respond to this Question

First Name

Your Response

Similar Questions

  1. physics

    8.01 homework. I have difficulty with question no. 2. all my equations do not work-Rough Surfaces. Also, the period of oscillation got part a the rest is confusing and my answers do not check out. I thought this was a very

    asked by Frank on October 16, 2013
  2. writing skills

    Do your homework before applying for any job. If you rewrote sentence 5 beginning with Be sure that you the next words should be 1 got done your homework 2 got your homework done 3 had done your homework 4 did your homework 5 have

    asked by piper on June 28, 2016

    The websites are confusing! Can someone please explain what a revenue variance is? I want to do my homework for a spreadsheet I downloaded. I just need the definition, please.

    asked by Donna needs help on May 17, 2010
  4. english

    Do your homework before applying for any job. if you rewrote the sentence beginning with (Be sure that you) the next words would be? 1)got done your homework 2)got your homework done 3)had done your homework 4)did your homework

    asked by Anonymous on May 10, 2010
  5. english

    I got a question regarding my homework. The task is to find the mistakes in a given text but the last sentence confuses me so much that I lost the overview. I'll copy the sentence below and hope that someone can help me. "But to

    asked by Leonie on October 26, 2014
  6. Damon *Algebra

    can you please break this equation down for me.I saw how you got 0,0 but im confusing my self on the rest of the problems such as 3x+2y=-8 2x-3y=-1 heres my answer (-2,-1) am i correct?

    asked by %%%Rena%%% on July 1, 2012
  7. spanish

    how do you say these words in spanish? notebook eraser cd player folders binder homework cellphone notebook-cuaderno eraser-borrador cd player-reproductor de compact-disc folders -carpetas binder-carpeta homework-deberes

    asked by kesha on November 16, 2006
  8. English

    I left out the following sentences.Thank you very much. 1) The day after Christmas my uncles from Liguria visited us. 2) The day after their visit I started my homework and I did't manage to finish it before the beginning of the

    asked by Henry2 on January 31, 2012
  9. psychology

    I need help bascially i didn't have time to jot down the homework so i'm not sure what the homework is about so...the only solution to this is to email my teacher but i don't know how to say it to her? Shall i say to her hello,

    asked by help on September 28, 2017
  10. Math

    Evaluate:|12 5 -2| |-3 0 1| |-5 4 2| It's going to be really confusing if I post my work. I got -127 from all the confusing things I did

    asked by Jon on February 26, 2008

More Similar Questions