Welcome to Westonci.ca, where curiosity meets expertise. Ask any question and receive fast, accurate answers from our knowledgeable community. Get detailed answers to your questions from a community of experts dedicated to providing accurate information. Get detailed and accurate answers to your questions from a dedicated community of experts on our Q&A platform.

What is the ph of a buffer made by combining 45. 0 ml of 0. 150 m nitrous acid and 20. 0 ml of 0. 175 m sodium nitrite? the ka of nitrous acid, hno2, is 4. 5×10^–4?

Sagot :

The pH of the buffer made by combining Nitrous acid and Sodium Nitrite will be 3.06.

pH can be defined as the medium of expressing the acidity or alkalinity of any solution. It is the potential of hydrogen atoms.

Buffers are the solutions that resist any change in the pH when an acid or base is added to them.

According to the question,

0.150 M nitrous acid (HNO₂) = 45 ml

0.175 M sodium nitrate (NO₂⁻)= 20 ml

Kₐ of nitrous acid (HNO₂) = 4.5 × 10⁻⁴

Total volume of buffer = 45 ml + 20 ml = 65 ml

Concentration of HNO₂ = (45) (0.150) / 65 = 0.103 M

Concentration of NO₂⁻ = (20) (0.175) / 65 = 0.054 M

                     HNO₂  ⇒ H⁺ + NO₂⁻

Initial :          0.103        0     0.054

Change:         -x             +x       +x

Equilibrium: 0.103-x        x       0.054+x

Kₐ = x(0.054+x) / 0.103-x = 0.054x / 0.103 = 0.524x

Also, Kₐ = 4.5 × 10⁻⁴

Therefore, 4.5 × 10⁻⁴ = 0.524x

                              x = 8.58 × 10⁻⁴ M

H⁺ = x = 8.58 × 10⁻⁴ M = 8.6 × 10⁻⁴ M

Therefore, pH = -log ( 8.6 × 10⁻⁴ M)

                 pH = 3.06

To know more about pH, here

brainly.com/question/2288405

#SPJ4

We appreciate your time. Please come back anytime for the latest information and answers to your questions. Thank you for your visit. We're committed to providing you with the best information available. Return anytime for more. Find reliable answers at Westonci.ca. Visit us again for the latest updates and expert advice.