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
luda_lava [24]
2 years ago
13

CH3COOH  CH3COO– + H+

Chemistry
1 answer:
Oxana [17]2 years ago
6 0

(a)

pH = 4.77

; (b)

[

H

3

O

+

]

=

1.00

×

10

-4

l

mol/dm

3

; (c)

[

A

-

]

=

0.16 mol⋅dm

-3

Explanation:

(a) pH of aspirin solution

Let's write the chemical equation as

m

m

m

m

m

m

m

m

l

HA

m

+

m

H

2

O

⇌

H

3

O

+

m

+

m

l

A

-

I/mol⋅dm

-3

:

m

m

0.05

m

m

m

m

m

m

m

m

l

0

m

m

m

m

m

l

l

0

C/mol⋅dm

-3

:

m

m

l

-

x

m

m

m

m

m

m

m

m

+

x

m

l

m

m

m

l

+

x

E/mol⋅dm

-3

:

m

0.05 -

l

x

m

m

m

m

m

m

m

l

x

m

m

x

m

m

m

x

K

a

=

[

H

3

O

+

]

[

A

-

]

[

HA

]

=

x

2

0.05 -

l

x

=

3.27

×

10

-4

Check for negligibility

0.05

3.27

×

10

-4

=

153

<

400

∴

x

is not less than 5 % of the initial concentration of

[

HA

]

.

We cannot ignore it in comparison with 0.05, so we must solve a quadratic.

Then

x

2

0.05

−

x

=

3.27

×

10

-4

x

2

=

3.27

×

10

-4

(

0.05

−

x

)

=

1.635

×

10

-5

−

3.27

×

10

-4

x

x

2

+

3.27

×

10

-4

x

−

1.635

×

10

-5

=

0

x

=

1.68

×

10

-5

[

H

3

O

+

]

=

x

l

mol/L

=

1.68

×

10

-5

l

mol/L

pH

=

-log

[

H

3

O

+

]

=

-log

(

1.68

×

10

-5

)

=

4.77

(b)

[

H

3

O

+

]

at pH 4

[

H

3

O

+

]

=

10

-pH

l

mol/L

=

1.00

×

10

-4

l

mol/L

(c) Concentration of

A

-

in the buffer

We can now use the Henderson-Hasselbalch equation to calculate the

[

A

-

]

.

pH

=

p

K

a

+

log

(

[

A

-

]

[

HA

]

)

4.00

=

−

log

(

3.27

×

10

-4

)

+

log

(

[

A

-

]

0.05

)

=

3.49

+

log

(

[

A

-

]

0.05

)

log

(

[

A

-

]

0.05

)

=

4.00 - 3.49

=

0.51

[

A

-

]

0.05

=

10

0.51

=

3.24

[

A

-

]

=

0.05

×

3.24

=

0.16

The concentration of

A

-

in the buffer is 0.16 mol/L.

hope this helps :)

You might be interested in
What is the IMA of the 1 st class lever in the graphic given?<br><br> 2<br> 3<br> 0.5
Zina [86]

Answer:

I believe the answer isT 2.

Explanation:

he formula for IMA of a first-class lever is effort-distance/resistance-distance.

6 0
3 years ago
Read 2 more answers
A gas occupies 18.5L at stp. what volume will it occupy at 735 torr and 57°c?
olga nikolaevna [1]

 The volume that  will  be occupied at 735  torr and 57 c  is 23.12 L


 <u><em>calculation</em></u>

  • <u><em> </em></u> At STP   temperature=273 k  and  pressure=760 torr
  • <u><em> </em></u>by use of combined  gas formula

that is P1V1/T1= P2V2/T2

where; P1 =760 torr

           T1= 273  K

           V1= 18.5 L

          P2= 735 torr

         T2=  57+273= 330 K

          V2=?

  • by making   V2 the formula of subject

     V2= T2P1V1/P2T1

       V2=  [(18.5L  x 330 k  x 760 torr)/(735 torr x 273 k)]= 23.12  L




5 0
3 years ago
A 23.6 ml of slat water has a mass of 26.47 grams. calculate its density.
bija089 [108]

The density is 1.12161 g/ml

7 0
2 years ago
How many moles are there in 67.2 grams of h2
yarga [219]

Answer: 33.3 moles

Explanation: 67.2 g H2 = 67.2/2.016 = 33.3 moles

7 0
3 years ago
If 200 ml of 0.15 M propionic acid (PA) is added to 300 ml of 0.02 M NaOH, what is the resulting pH of the solution? Round the a
vodomira [7]

Answer:

pH = 4.543

Explanation:

  • CH3CH2COOH  + H2O ↔ CH3CH2COO-  +  H3O+
  • pKa = - Log Ka

∴ Ka = [H3O+][CH3CH2COO-]/[CH3CH2COOH]

∴ pKa = 4.87

⇒ Ka = 1.349 E-5 = [H3O+][CH3CH2COO-]/[CH3CH2COOH]

added 300 mL 0f 0.02 M NaOH:

⇒ <em>C</em> CH3CH2COOH = ((0.200 L)(0.15 M)) - ((0.300 L)(0.02 M))/(0.3 + 0.2)

⇒ <em>C</em> CH3CH2COOH = 0.048 M

⇒ <em>C</em> NaOH = (0.300 L)(0.02 M) / (0.3 +0.2) = 0.012 M

mass balance:

⇒ 0.048 + 0.012 = 0.06 M = [CH3CH2COO-] + [CH3CH2COOH].......(1)

charge balance:

⇒ [H3O+] + [Na+] = [CH3CH2COO-]

∴ [Na+] = 0.02 M

⇒ [CH3CH2COO-] = [H3O+] + 0.02 M.............(2)

(2) in (1):

⇒ [CH3CH2COOH] = 0.06 M - 0.02 M - [H3O+] = 0.04 M - [H3O+]

replacing in Ka:

⇒ 1.349 E-5 = [H3O+][([H3O+] + 0.02) / (0.04 - [H3O+])

⇒ (1.349 E-5)(0.04 - [H3O+]) = [H3O+]² + 0.02[H3O+]

⇒ 5.396 E-7 - 1.349 E-5[H3O+] = [H3O+]² + 0.02[H3O+]

⇒ [H3O+]² + 0.02001[H3O+] - 5.396 E-7 = 0

⇒ [H3O+ ] = 2.867 E-5 M

∴ pH = - Log [H3O+]

⇒ pH = 4.543

3 0
3 years ago
Other questions:
  • Sn4+(aq) + 2e− → sn2+(aq)which term best describes this reaction?ionizationneutralizationoxidationreduction
    11·1 answer
  • How many secondary (2°) carbons are found in 5-ethyl-3,3,4-trimethylheptane??
    7·2 answers
  • The p K b pKb values for the dibasic base B B are p K b1 = 2.10 pKb1=2.10 and p K b2 = 7.84 . pKb2=7.84. Calculate the pH at eac
    11·1 answer
  • ***30 POINTS!!!!
    7·1 answer
  • The boiling point elevation of an aqueous sucrose is found to be 0.39 Celsius. What mass of sucrose (molar mass = 342.30g/mol) w
    13·1 answer
  • The half-life of thorium-227 is 18.72 days. How many days are required for three-fourths of a given amount to decay?
    5·1 answer
  • Which half-reaction correctly represents reduction?
    8·1 answer
  • Pls help me it detects if it’s right or wrong
    13·1 answer
  • Explain how atomic number relates to the number of particles in an atom’s nucleus.
    12·1 answer
  • Which organ gives our body the sense to touch, protects it, and helps keep it at the right temperature?
    8·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!