Lab 5

LAB REPORT No 5

NAME_______________________________ DATE________________

1. Measuring the pH value of some compounds.

Solution

pH by Litmus paper

pH by Hydrion paper

pH by pH meter

Acid, Basic or Neutral

1% NH4OH

2% Ethanoic Acid

Distilled water

1% HCl

1% NaOH

2. Buffers.

pH of water

pH of buffer solution

Initial

After five drops NaOH

After ten drops NaOH

Which solution best resists the pH change? Explain your answer.

3. Concentration of Acetic Acid in Vinegar. Sample N0______.

Test tube

Number of NaOH drops

%(m/v) of acetic acid in vinegar

1

2

3

4

Average percentage of acetic acid in vinegar %(m/v)

Questions:

1. What is the difference between a strong acid and a weak acid? Explain and use examples of each type of acid.

2. Give examples of:

a- An Acid Buffer (two components).

b- A Basic Buffer (two components).

3. Complete the table given bellow:

[H3O+1]

[OH-1]

pH

Acidic, basic or neutral

1.0 x 10-3

5

3.0 x 10-6

neutral

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No. 5 LAB REPORT

NAME_______________________________ DATE________________

1. Determining the pH of certain substances.

Solution

Litmus paper pH test

Hydrion paper pH

pH measurement using a pH meter

Neutral, acidic, or basic

One percent NH4OH

Ethanoic acid at 2%

Water from a distillery

1% hydrochloric acid

NaOH (1%).

2. The buffers.

Water’s pH

buffer solution’s pH

Initial

NaOH after five drops

Following 10 drops of NaOH

Which solution is the most resistant to pH change? Explain your response.

3. Concentration of Acetic Acid in Vinegar. Sample N0______.

Test tube

Number of NaOH drops

%(m/v) of acetic acid in vinegar

1

2

3

4

Average percentage of acetic acid in vinegar %(m/v)

Questions:

1. What is the difference between a strong acid and a weak acid? Explain and use examples of each type of