Question

18. Which H3O+ concentration and classification (acidic vs. basic) are correctly matched for a solution in which the OH- concentration is 5.6 x 10-6 M?

a. 5.6 x 10^{-6} M : basic

b. 5.6 x 10^{-6} M : acidic

c. 5.6 x 10^{8} M : acidic

d. 1.8 x 10^{-9} M : basic

e. 1.8 x 10^{-9} M : acidic

19. The solution that will give a pH = 12.00 is (MW: NaOH = 40 g/mol):

a. 4.0 g NaOH in 1.0 L of solution.

b. 12 g NaOH in 1.0 L of solution.

c. 0.20 g NaOH in 2.0 L of solution.

d. 0.20 g NaOH in 0.50 L of solution.

e. 0.40 g NaOH in 0.10 L of solution.

20. What is the K_{a} of the weak acid HClO_{2}
if a 0.100 M solution of the acid has a pH = 2.22?

a. 3.6 x 10^{-4}

b. 6.0 x 10^{-3}

c. 1.6 x 10^{-3}

d. 5.9 x 10^{-4}

e. 1.3 x 10^{-2}

Answer #1

[OH-] = 5.6*10^-6

since 10^-7 < [OH]

[H+] = 10^-14)/( 5.6*10^-6) = 1.78571*10^-9

then

this is BASIC

19. The solution that will give a **pH = 12.00** is
(MW: NaOH = 40 g/mol):

pOH = 14-12 = 2

pOH = -log(OH-)

[OH-] = 10^-2

0.01 mol of NaOH per liter

0.4 g of NaOH per liter

a. 4.0 g NaOH in 1.0 L of solution. --> NOT

b. 12 g NaOH in 1.0 L of solution. --> NOT

c. 0.20 g NaOH in 2.0 L of solution. --> TRUE

d. 0.20 g NaOH in 0.50 L of solution. --> TRUE

e. 0.40 g NaOH in 0.10 L of solution. --> NOT

1.What volume of a 1.50 M NaOH solution should be added to 50.0
mL of 1.20 M acetic acid (CH3CO2H;
Ka = 1.76×10-5) to obtain a buffer with pH =
5.450?
a) 33.3 mL
b) 6.70 mL
c) 16.4 mL
d) 67.0 mL
e) 42.1 mL
2. Find the concentration of hydronium ion,
H3O+, in a 0.200 M solution of sodium
hypochlorite, NaOCl.
Ka(HOCl) = 3.0×10-8.
a) 7.8×10-5 M
b) 1.3×10-10 M
c) 1.0×10-7 M
d) 3.9×10-11 M
e) 2.6×10-4...

calculate [H3O+], [OH-], for each of the following. Label the
solution acidic, basic, or neutral
1. 0.01 M HCl
2. 0.033 M HNO3
3. 0.0045 M NaOH
4. 10 M HCl
5. 2.7 M NaOH

The solution that will give a pH = 12.00 is (MW: NaOH = 40
g/mol):
A. 4.0 g NaOH in 1.0 L of
solution.
B. 12 g NaOH in 1.0 L of
solution.
C. 0.20 g NaOH in 2.0 L of
solution.
D. 0.20 g NaOH in 0.50 L of
solution.
E. 0.40 g NaOH in 0.10 L of
solution.

For each of the following, is the solution acidic, basic,
neutral, or cannot be determined? For each, write the equation for
the dominant equilibrium which determined the pH, and justify your
pH prediction. Kw = 1.0 x 10-14
100 mL of 0.10 M NaH3P2O7; Ka1 = 3.0 x 10-2, Ka2 = 4.4 x 10-3,
Ka3 = 2.5 x 10-7, and Ka4 = 5.6 x 10-10 for H4P2O7.

5. (6 pts) The pH of an acetic acid (CH3COOH) solution is 6.20.
Calculate the concentration
of hydronium ion (H3O+, in M) in this solution. (Ka = 1.8 x
10–5)
3
For questions 6-8, consider the titration of of 5.00 mL of 0.450 M
HBr using 0.120 M NaOH as
the Btrant.
6. (6 pts) Calculate the volume of 0.120 M NaOH that must be added
in order to reach the
equivalence point.

20. Calculate the molarity of hydroxide ion in an
aqueous solution that has a pOH of 5.00
[A] 1.0 ⋅ 10-9 [B] 1.0 ⋅ 10-5
[C] 9.0 ⋅ 10-14 [D] 9.00 [E] 5.0 ⋅10-14
21. What is the pOH of an aqueous solution at 25.0
°C that contains 3.98 ⋅ 10-9 M hydronium ion?
[A] 9.000 [B] 5.600 [C] 3.980 [D] 7.000 [E]
8.400
22. Which solution will be the most basic?
[A] 0.20 M Sr(OH)2...

Calculate the value of [H3O+] from the given [OH-] and lable the
solution as acidic or basic.
A. 10^-2 M
B. 4.0 x 10^-8 M
C. 6.2 x 10^-7 M
D. 8.5 X 10^-13 M

Complete the following table.
(All solutions are at 25 ∘C.)
[H3O+]
[OH−]
pH
Acidic or Basic
3.5×10−3
_____
_____
_____
_____
3.8×10−7
_____
_____
1.8×10−9
_____
_____
_____
_____
_____
7.15
_____
[H3O+]2, [H3O+]4 =
[OH−]1, [OH−]3, [OH−]4 =
pH1, pH2, pH3, =
Complete the fourth column.
Enter your answers separated by commas.

Complete the following table:
H3O+
OH−
pH
Acidic, Basic, or Neutral?
10.0
Neutral
4×10−5M
1 ×10−2M
12.2
Part A
If the pH of the solution is 10.0, what is the [H3O+]?
Express your answer to one significant figure.
[H3O+] =
M
Part B
If the pH of the solution is 10.0, what is the [OH−]?
Express your answer to one significant figure.
[OH−] =
M
Part C
If the solution is neutral, what is the [H3O+]?
Express your answer to...

1. Assuming a negligible change in volume, how many moles of
H3O+ or OH– must you add per litre to an acidic solution to adjust
its pH from 5.80 to 6.25?
(A) 1.58 x 10–6 mol H3O+
(B) 2.14 x 10–6 mol OH–
(C) 1.02 x 10–6 mol H3O+
(D) 1.02 x 10–6 mol OH–
(E) 2.14 x 10–4 mol H3O+
2.. A buffer is prepared by mixing 100.0 mL of a 0.100 mol L–1
CH3COOH solution with a 0.200...

ADVERTISEMENT

Get Answers For Free

Most questions answered within 1 hours.

ADVERTISEMENT

asked 7 minutes ago

asked 9 minutes ago

asked 10 minutes ago

asked 12 minutes ago

asked 17 minutes ago

asked 17 minutes ago

asked 18 minutes ago

asked 20 minutes ago

asked 22 minutes ago

asked 26 minutes ago

asked 39 minutes ago

asked 45 minutes ago