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
iren [92.7K]
3 years ago
14

What mass of sodium benzoate should be added to 150.0 ml of a 0.15 m benzoic acid solution in order to obtain a buffer with a ph

of 4.25? (assume no volume change.)?
Chemistry
1 answer:
Monica [59]3 years ago
3 0
When we know the Pka value = 4.19 

so, we are going to use H-H equation:

PH = Pka + ㏒[benzoate/benzoic acid]

when we have PH = 4.25 

and Pka = 4.19 

so by substitution:

4.25 = 4.19 + ㏒[benzaoate/ benzoic acid]

∴ [benzaoate/benzoic acid] = 1.148 M

when the [benzoic acid ] = 0.15 m 

∴ [benzaoate] = 1.148M * 0.15m 

                        = 0.1722 M

∴ moles of sodium benzoate = molarity * volume L

                                                 = 0.1722 M * 0.15 L 

                                                 = 0.02583 moles

∴ the mass = moles * molar mass

                   = 0.02583 moles* 144 g/mol

                   = 3.72 g


You might be interested in
What elements make up most of the mantle?
amid [387]
44.8% oxygen, 21.5% silicon, and 22.8% magnesium. There's also iron, aluminum, calcium, sodium, and potassium. These elements are all bound together in the form of silicate rocks, all of which take the form of oxides.
8 0
3 years ago
Why do scientists continue to investigate certain topics like the atom?
Margaret [11]

Answer:

to understand the human life

Explanation:

hope this helps :)

5 0
3 years ago
Read 2 more answers
A 15.00 % by mass solution of lactose (C 12H 22O 11, 342.30 g/mol) in water has a density of 1.0602 g/mL at 20°C. What is the mo
Alik [6]

Answer:

22.82M

Explanation:

342.3g/mol is présent in 1000

what about in 15??

( 342.3g/mol × 1000 ) ÷ 15

3 0
2 years ago
How many atoms of manganese are in 1.00 g?
andriy [413]

Answer:

\frac{1.00g}{54.9g. {mol}^{ - 1} }  =  0.0182\: mol\\  \\ 6.023 \times  {10}^{23}   \times 0.0182 \: mol  \\ = 0.109\times  {10}^{23} \: atoms

8 0
3 years ago
Read 2 more answers
What r rocks made of
Iteru [2.4K]
Most are made from crystals and minerals.
6 0
3 years ago
Read 2 more answers
Other questions:
  • Which is an example of a chemical change?
    8·1 answer
  • In your bathroom you leave the faucet dripping. If the faucet leaks 30.0 drops/minute, how much water will you waste after 3.00
    8·1 answer
  • List the numbers of each atom in all the formulas above: <br> H <br> C
    15·2 answers
  • Light strikes a beautiful white perch under water. This light is reflected back to your eyes allowing you to see the fish. As th
    12·1 answer
  • Two mixed cylinders have exactly the same volume. Cylinder A has a higher fraction of Al than cylinder B. Is the mass of cylinde
    6·1 answer
  • What is an example of radioactive decay
    7·1 answer
  • Draw arrows for all of the attractive and repulsive forces between the negatively charged electrons and positively charged proto
    15·1 answer
  • A 73.6 g sample of aluminum is heated to 95.0°C and dropped into 100.0 g of water at 20.0°C. If the resulting temperature of the
    8·1 answer
  • Please help me immediately!!!
    14·1 answer
  • Any expert know what is the answer?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!