1. Acids, Bases, & ph Lab Page 101

2. Red cabbage waterRed cabbage water is an indicator of pH. Although it can't be used to determine exact pH, it can distinguish between acid (pH of 0 to 6), neutral (pH near 7), and base (pH of 8 to 14).  acid neutral base 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14  2. In this activity:  If the indicator turns the solution red or pink, the solution is an acid.  A purple solution indicates that it is neutral, neither an acid nor a base.  If the indicator turns the solution blue or green, the solution is a base.

3.  1. What is the role of a pH indicator? The measurement of how much acid or base is in a solution.  2a.The range of pH: (cabbage juice) red or pink = an acid. purple = neutral blue or green=base.  2b. Red Litmus Paper If the red litmus paper turns red, then its neutral or an acid.  2c. Blue Litmus Paper If the blue litmus paper turns blue, then it’s neutral or a base.

4. Acids & Bases  1. Which of your solutions has the highest concentration of H+ ions? Lemon, vinegar, apple juice, and mystery solution A (hydrogen peroxide) Lemon is the highest!!  2. Explain your reasoning: An acidic solution contains an excess of protons or H+.

5.  3. Which has the highest concentration of OH– ions? Seltzer, baking soda, bar soap, anti- bacterial cleaner, Bar Soap is the greatest base!!  4. Explain your reasoning: Basic solutions release OH - ions in a solution.

6. Red cabbage juice  5. The red cabbage juice is used in the Investigations has 2 roles: pH indicator control.  Why is a control needed on the pH test plate?  Control is the substance that stays the same in each trial. It is used to measure the differences between the other solutions.

7. Mystery solutions A & B are identical to 2 other solutions you used in this lab. Use your results to identify these solutions.  1. What is the identity of mystery solution List evidence to support your claim  2. What is the identity of mystery solution B List evidence to support your claim:

9.  Claim A statement about the solution to the problem (a statement of hypothesis).  Evidence The scientific data that supports the claim.  Reasoning Justification that shows why the data counts as evidence to support the claim. It includes appropriate scientific principles.