MiniLab - Determine pHMiniLab - Determine pH

The pH of a solution is a measurement The pH of a solution is a measurement of how acidic or basic that solution is.of how acidic or basic that solution is.

An easy way to measure the pH of a An easy way to measure the pH of a solution is to use pH paper.solution is to use pH paper.

ProcedureProcedure1.1. You will be testing lemon juice, ammonia, You will be testing lemon juice, ammonia,

liquid detergent, shampoo, vinegar, and liquid detergent, shampoo, vinegar, and an unknown.an unknown.

2.2. Dip a fresh strip of pH paper briefly into Dip a fresh strip of pH paper briefly into each solution and remove.each solution and remove.

3.3. Compare the color of the wet paper with Compare the color of the wet paper with the pH color chart; record the pH of each the pH color chart; record the pH of each substance.substance.

Data table of common Data table of common household productshousehold products

SubstanceSubstance Acid Acid or or base?base?

Actual Actual pHpH

Actual Actual acid or acid or base?base?

1 - Lemon 1 - Lemon juicejuice

2 - Antacid2 - Antacid

3 - Detergent3 - Detergent

4 – window 4 – window cleanercleaner

5 - Vinegar5 - Vinegar

6 - Unknown6 - Unknown

Analysis: Analysis: Do NOT copy the question. Answer the Do NOT copy the question. Answer the

questions in complete sentences.questions in complete sentences.

1.1. Which of the solutions are acids?Which of the solutions are acids?

2.2. Which solutions are bases?Which solutions are bases?

3.3. What ions in the solution caused What ions in the solution caused the pH paper to change? Which the pH paper to change? Which solution contained the highest solution contained the highest concentration of hydroxide ions? concentration of hydroxide ions? How do you know?How do you know?

Analysis: Analysis: Answer the questions in complete sentences.Answer the questions in complete sentences.

4.4. Why is it important for us to know the Why is it important for us to know the effect of acidic and basic substances on effect of acidic and basic substances on the human body?the human body?

5.5. Give examples of human conditions that Give examples of human conditions that result from too much acid in the body.result from too much acid in the body.

6.6. What do you think is the unknown?What do you think is the unknown?