19.2 Lesson: pH concept

​How does one compares the strengths of acids or bases?

​pH scale measures the strength of acids according to the concentration of H⁺ ions.

Multiple Choice

A(n) ______ is a substance with a pH less than 7

• Acid

• Alkaline

• Base

• Buffer

Multiple Choice

A(n) _______ is a substance with a pH greater than 7.

• Base

• Acid

• Buffer

• Water

Multiple Choice

What is the only substance with a neutral pH of 7?

• Milk

• Orange Juice

• Water

• Blood

Multiple Choice

On the pH scale higher numbers indicate

• acids

• bases

​Explanation: The [H⁺] is orange juice is
0.00020 M.  Find the pH of orange juice.

• ​Use the equation pH= -log[H⁺].

• Substitute in [H⁺] with 0.00020.

• Solve pH = -log [0.00020] = 3.70

Multiple Choice

The [H⁺] is orange juice is
0.00020 M.  FInd the pH of orange juice.

• 1

• 3.7

• 10.3

• 13

Multiple Choice

If the [H+] of a solution is 6.8 x 10^-9 M then pH is

• 8.17

• 8.2

• 9.99

• 8.62

Multiple Choice

What is the pH of a solution that has a [H+] of 2.5 x 10-5?

4.605.02.57

• 4.6

• 5.0

• 2.5

• 7.0

Multiple Choice

What is the [OH-] if the pH is 4.9?

• 7.94 x 10-10 M

• 1.0 x 10-4 M

• 7.94 x 10-14 M

• 4.9 x 10-10 M

Multiple Choice

What is the [OH-] if the [H+] is 1.0 x 10-3 M?

• 1.0 x 10-3 M

• 6.02 x 10-23 M

• 1.0 x 10-14 M

• 1.0 x 10-11 M

Multiple Choice

What is the pOH of a 1 x 10^-8 M solution of HNO₃?

• 8

• 6

• 7

• 9