1. Chemical/Physical Properties & pH
7.P.2B.3 Analyze and interpret data to compare the physical properties, chemical properties (neutralization to form a salt, reaction with metals), and pH of various solutions and classify solutions as acids or bases.

2. Physical Properties
You should already know that:
Physical properties can be observed without changing the composition of the substance.

3. Chemical Properties
You should already know that:
Chemical properties can ONLY be observed by changing the composition of the substance, forming new substances.

4. pH Scale
A tool that is used to measure how acidic or alkaline (basic) something is.
Measures from 0 to 14.

5. Acids
Acidic solutions have a pH between 0 and 6.
Chemical formulas usually start with H
Examples of acids:

6. Bases
Alkaline (basic) solutions have a pH between 8 and 14.
Chemical formulas usually end in OH
Examples of bases:

7. Neutrals
Neutral solutions have a pH of 7.
Example of neutral:

8. Chemical Properties of ACIDS
React with some metals to give off a gas
Neutralization occurs when acids and bases react with each other. They can form a salt and usually water.

9. Chemical Properties of ACIDS
React with blue litmus paper turning it red
Does not react with red litmus paper and the litmus paper will remain red.
Doesn’t react with phenolphthalein

10. Physical Properties of ACIDS
Tastes sour
Sticky texture

11. Chemical Properties of BASES
Neutralization occurs when bases and acids react with each other. They can form a salt and usually water.
React with red litmus paper turning it blue.

12. Chemical Properties of BASES
Does not react with blue litmus paper and the litmus paper will remain red.
Reacts with phenolphthalein turning it magenta (pink)

13. Physical Properties of BASES
Tastes bitter
Slippery texture

14. Chemical Properties of NEUTRALS
Are formed when neutralization occurs between acids and bases.
Neither an acid nor a base.

15. Chemical Properties of NEUTRALS
Reacts with litmus paper turning it violet.
Reacts with phenolphthalein turning it magenta (pink).

16. Indicators
Substances that can be used to determine if a solution is acidic, basic, or neutral.
Litmus Paper Phenolphthalein pH Paper

17. Litmus Paper
Has a special dye on it that changes colors in the presence of an acid or base.
Blue litmus paper turns red in an acid, and stays blue in a base.
Red litmus paper turns blue in a base, and stays red in an acid.

18. Phenolphthalein
Is used to test for the presence of a base.
It is a colorless chemical that turns magenta (bright pink) in a base, and stays colorless in neutral or acidic solutions.

19. pH paper
Has a range of colors depending on the pH of the solutions
The color of the paper is compared to the chart on the vial to determine the pH