Determine the pH of a 0.500 M HNO2 solution. Ka of HNO2 is 4.6 * 10-4. 1.82 1.67 2.67 0.30

Free

90.2K

Verified Solution

Question

Chemistry

Determine the pH of a 0.500 M HNO2 solution. Ka of HNO2is 4.6 * 10-4.
1.82
1.67
2.67
0.30

Answer & Explanation Solved by verified expert

4.3 Ratings (911 Votes)

Write the reaction of HNO2 with water and set up the ICE

Â Â Â Â Â Â Â Â Â Â Â HNO2 (aq) + H2O (l)Â Â Â ---- > NO2- (aq) + H3O + (aq)

IÂ Â Â Â Â Â Â 0.500Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 0Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â 0

CÂ Â Â Â Â Â Â Â Â -xÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â +xÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â +x

EÂ Â Â Â Â Â Â Â (0.500-x)Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â xÂ Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â x

Use ka expression to find the value of x

Ka = 4.6 x 10^-4 = x²/ ( 0.500-x)

Solve quadratic equation.

X² = 4.5 x 10^-4 ( 0.500-x)

x = 0.01478 = [H3O+]

we know pH = - log [H3O+]

therefore

pH = - log ( 0.01478)

= 1.82

So the pH = 1.82

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member