1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
katovenus [111]
3 years ago
13

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer so

lution with an optimum pH of 9.2−9.3? CH3COONa/CH3COOH (Ka = 1.8 x 10^−5) NH3/NH4Cl (Ka = 5.6 x 10^−10) NaOCl/HOCl (Ka = 3.2 x 10^−8) NaNO2/HNO2 (Ka = 4.5 x 10^−4) NaCl/HCl
Chemistry
1 answer:
BartSMP [9]3 years ago
4 0

Answer:

NH₃/NH₄Cl

Explanation:

We can calculate the pH of a buffer using the Henderson-Hasselbalch's equation.

pH=pKa+log\frac{[base]}{[acid]}

If the concentration of the acid is equal to that of the base, the pH will be equal to the pKa of the buffer. The optimum range of work of pH is pKa ± 1.

Let's consider the following buffers and their pKa.

  • CH₃COONa/CH3COOH (pKa = 4.74)
  • NH₃/NH₄Cl (pKa = 9.25)
  • NaOCl/HOCl (pKa = 7.49)
  • NaNO₂/HNO₂ (pKa = 3.35)
  • NaCl/HCl Not a buffer

The optimum buffer is NH₃/NH₄Cl.

You might be interested in
Why are koalas so crusty?
marishachu [46]
Koalas are not crusty, but their fur is very coarse, like wool.
Hope this helps.
6 0
4 years ago
Read 2 more answers
How can you determine the number of atoms in a mole of a molecular compound
Brilliant_brown [7]
Well if you go to Quiz-let it gives the answer the mass of a mole of compound is determined by adding the atomic masses of the atoms making up the molecules
7 0
3 years ago
How does the amount of carbon dioxide affect the rate of photosynthesis?
swat32

Answer:

An increase in the carbon dioxide concentration increases the rate at which carbon is incorporated into carbohydrate in the light-independent reaction, and so the rate of photosynthesis generally increases until limited by another factor.

Explanation:

4 0
2 years ago
Read 2 more answers
1/ Which graph illustrates constant speed and velocity
Maksim231197 [3]
Velocity is said to be constant if its magnitude as well direction at any instant is remains the same. In D, if you draw a line parallel to y-axis at any time t, you can see that velocity is same. Hence, D is the correct graph.

The kinetic energy of gaseous molecules is greater than that of liquid molecules. Therefore, in gas, kinetic energy overcomes the force of attraction between molecules. In short, in gas phase, particles move at high speed and hence they have less force of attraction. In case of liquid phase, particles are close enough as a result there is much more force of attraction compared to gaseous molecules. In liquid state, kinetic energy cannot overcome force of attraction therefore, liquid molecules slow down.

Therefore, B is the correct answer.
4 0
4 years ago
"sodium hydroxide is a strong base because it absorbs more" ____________ ions than weak bases.
Hunter-Best [27]
The answer is: absorbs more H (protons) ions.

- The Sodium hydroxide NaOH ionizes completely when dissolved in water.
- For every mole of sodium hydroxide that you dissolve you get 1 mole of hydroxide anions.
4 0
3 years ago
Read 2 more answers
Other questions:
  • Bromocresol green, Ka=2.0×10−5, is yellow in its protonated form (HX) and blue in its ionized form (X−). At what pH will bromocr
    8·1 answer
  • Which one of the following is the net ionic equation for the reaction of nitric acid with aluminum hydroxide
    14·1 answer
  • When you compress a spring, which type of energy increase
    7·1 answer
  • Why do you think humpback whales sing
    5·1 answer
  • Which of th following is true for a parallel circuit
    8·1 answer
  • Calculate the volume in cm^3 of 325.0 dg of alcohol. Alcohol has a density of 0.785g/mL.
    12·1 answer
  • Arthur is performing a lab which requires a 0.2 M solution of calcium hydroxide. However, the only calcium hydroxide solution av
    12·1 answer
  • Which of the following best describes a single-replacement reaction?
    8·1 answer
  • Which of the following is another term for eruptions of gas on the sun's surface?
    9·1 answer
  • . Consider the following half-reactions:
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!