Question

for each of the following Solutions calculate the initial pH in the final pH after adding 0.200 moles of NaOH for

300.0 M L of a buffer solution that is 0.2551 m in
ch3ch2nh2 AND 0.2351 in ch3ch2nh3cl calculate the initial pH and
the final pH after adding 0.020 moles of naoh KB equal 5.6 x 10 to
the negative 4

Answer #1

Given that,

[CH3CH2NH2] = 0.2551

[CH3CH2NH3Cl] = 0.2351

Kb = 5.6*10^-4

pKb = - log Kb

= 3.25

We know that pKa+ pKb = 14

pKb = 14-3.25

= 10.75

Now use the Henderson Hasselbalch eqn. to calculate the pH

pH = pKa + log([CH3CH2NH2] / [CH3CH2NH3Cl])

= 10.75 + log(0.2551/0.2351)

= 10.75 + log 1.085

= 10.75 + 0.035

= 10.785

now calculate the Final pH after adding 0.0200 moles NaOH:

Number of mole s= volume in L * molarity

moles CH3CH2NH2 = 0.300 L x 0.2551 M = 0.07653

moles CH3CH2NH3Cl = 0.300 L x 0.2351M = 0.07053

CH3CH2NH3+ + OH- = CH3CH2NH2 + H2O

moles CH3CH2NH3+ = 0.07053 - 0.0200= 0.05053

moles CH3CH2NH2 = 0.07653+ 0.0200 = 0.09653

now calculate new molarity as follows:

[CH3CH2NH3+] = 0.05053/ 0.300 = 0.1684 M

[CH3CH2NH2] = 0.09653 /0.300 L = 0.3218 M

pH = 10.75 + log(0.3218 / 0.1684)

=10.75+ 0.281

**= 11.031**

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.0100 mol of NaOH.
Part A
For 300.0 mL of pure water, calculate the initial pH and the
final pH after adding 0.0100 mol of NaOH.
Express your answers using two decimal places separated by a
comma.
Part B
For 300.0 mL of a buffer solution that is 0.210 M in
HCHO2 and 0.280 M in KCHO2, calculate the initial pH and
the final...

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.0150 mol of NaOH.
For 270.0 mL of pure water, calculate the initial pH and the
final pH after adding 0.0150 mol of NaOH.
For 270.0 mL of a buffer solution that is 0.240 M in
HCHO2 and 0.310 M in KCHO2, calculate the initial pH and
the final pH after adding 0.0150 mol of NaOH(Ka=1.8⋅10−4).
For 270.0 mL of a buffer solution that...

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.005 mol of NaOH.
For 260.0 mL of a buffer solution that is 0.265 M in
CH3CH2NH2 and 0.235 M in CH3CH2NH3Cl, calculate the
initial pH and the final pH after adding 0.005 mol of NaOH.

For each of the following solutions, calculate the
initial pH and the final pH after adding 0.0200 mol of
NaOH.
Part A
For 290.0 mL of pure water, calculate the initial pH and the
final pH after adding 0.0200 mol of NaOH.
Express your answers using two decimal places separated by a
comma.
Answer: pHinitial, pHfinal = 7.00,12.84
Part B
For 290.0 mL of a buffer solution that is 0.200 M in
HCHO2 and 0.310 M in KCHO2, calculate the...

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.010 mol of NaOH.
c) For 220.0 mL of a buffer solution that is 0.285 M in
CH3CH2NH2 and 0.255 M in CH3CH2NH3Cl, calculate the
initial pH and the final pH after adding 0.010 mol of NaOH.

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.010 mol of NaOH .
Part B
250.0 mL of a buffer solution that is 0.200 M in HCHO2 and 0.305
M in KCHO2
Part C
250.0 mL of a buffer solution that is 0.265 M in CH3CH2NH2 and
0.245 M in CH3CH2NH3Cl
Express your answers using two decimal places separated by a
comma.

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.010 mol of NaOH.
For 300.0mL of pure water, calculate the initial pH and the
final pH after adding 0.010 mol of NaOH.
For 300.0mL of a buffer solution that is 0.240M in
HCHO2 and 0.280M in KCHO2, calculate the initial pH and
the final pHafter adding 0.010 mol of NaOH.
For 300.0mL of a buffer solution that is 0.305M in
CH3CH2NH2 and 0.285M...

Exercise 16.50
For each of the following solutions, calculate the initial pH
and the final pH after adding 0.0200 mol of NaOH.
Part A
For 300.0 mL of pure water, calculate the initial pH and the
final pH after adding 0.0200 mol of NaOH.
Express your answers using two decimal places separated by a
comma.
pHinitial, pHfinal =
7.00,12.82
SubmitMy AnswersGive
Up
Correct
Part B
For 300.0 mL of a buffer solution that is 0.210 M in
HCHO2 and 0.310...

For each of the following solutions, calculate the initial pH
and the final pH after adding 0.010 mol of NaOH.
Part A: For 270.0 mL of a buffer solution that is 0.205 M in
HCHO2 and 0.305 M in KCHO2, calculate the initial pH and the final
pH after adding 0.010 mol of NaOH. Express your answers using two
decimal places separated by a comma.
Part B: For 270.0 mL of a buffer solution that is 0.285 M in
CH3CH2NH2...

For each of the following solutions, calculate the initial pHand
the final pH after adding 0.005 mol of NaOH.
260.0 mL of a buffer solution that is 0.225 M in HCHO2 and 0.315
M in KCHO
260.0 mL of pure water
260.0 mL of a buffer solution that is 0.275 M in CH3CH2NH2 and
0.245 M in CH3CH2NH3Cl

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 6 minutes ago

asked 20 minutes ago

asked 58 minutes ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 1 hour ago

asked 2 hours ago

asked 2 hours ago

asked 2 hours ago