Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

1.What is the pH of a solution that has [OH - ] = 4.0 ´ 10 9 M ? 8.40 5.60 4.60

ID: 103087 • Letter: 1

Question

1.What is the pH of a solution that has [OH-] = 4.0 ´ 109 M?

8.40

5.60

4.60

9.40

none of these

2.Choose the case that is not a conjugate acid-base pair.

H3O+, H2O

H3PO4, HPO42-

OH-, O2

NH2OH2+, NH2OH

HCO3-, CO32

3.Calculate the [H+] in a solution that has a pH of 5.21.

1.6 ´ 109 M

6.2 ´ 106 M

4.0 ´ 103 M

1.6 ´ 102 M

none of these

4.A 51.24-g sample of Ba(OH)2 is dissolved in enough water to make 1.20 L of solution. How many milliliters of this solution must be diluted with water in order to make 1.00 L of 0.100 M Ba(OH)2?

1.20 ´ 103 mL

400. mL

278 mL

333 mL

none of these

5.How many grams of NaCl are contained in 350. mL of a 0.250 M solution of sodium chloride?

5.11 g

87.5 g

14.6 g

41.7 g

none of these

a.

8.40

b.

5.60

c.

4.60

d.

9.40

e.

none of these

Explanation / Answer

1)

we have below equation to be used:

pOH = -log [OH-]

= -log (4*10^-9)

= 8.40

we have below equation to be used:

PH = 14 - pOH

= 14 - 8.40

= 5.60

Answer: b

Only 1 question at a time please