Test the effects of pH on living systems. Outcome: Test the effects of pH on living systems. Warm Up: Lemon Juice has a pH of 2, while tomato juice has a pH of 4. Which of these statements is true? A. Lemon juice is 20 times more acidic than tomato juice. B. Lemon juice is 100 times more acidic than tomato juice. C. Tomato juice is 20 times more acidic than lemon juice. D. Tomato juice is 100 times more acidic than lemon juice. pH [H+] [OH_] 14 1 10,000,000 13 1,000,000 12 100,000 11 10,000 10 1,000 9 100 8 7 6 5 4 3 2

Test the effects of pH on living systems. Outcome: Test the effects of pH on living systems. Design a controlled experiment to test a hypothesis. Collect and analyze data. Use evidence to support a claim. Warm Up: Lemon Juice has a pH of 2, while tomato juice has a pH of 4. Which of these statements is true? A. Lemon juice is 20 times more acidic than tomato juice. B. Lemon juice is 100 times more acidic than tomato juice. C. Tomato juice is 20 times more acidic than lemon juice. D. Tomato juice is 100 times more acidic than lemon juice.

Today’s Plan Real world reading pH Summative Assessment Design a data table to record your data. Design a graph. Check seed growth. Add today’s data to your graph. If no seed growth, add more drops and put back in the bag… consider making your paper towel smaller, but the same size for each bag. Use the checklist to analyze your progress. Scientific Notation Worksheet and slides Control BCR or Carbohydrate Model Closing

Scientific Method & Lab Report The steps of the “scientific method” are to: Make an observation Construct a hypothesis Test your hypothesis by doing an experiment Analyze your data and draw a conclusion Conclusion - Report your results

Which seeds sprouted more? Class DATA Strong Acid Weak Acid Neutral Weak Base Strong Base

Sources of Error

Importance of Control BCR Balloon A group of students wants to determine whether a gas is released when glucose is added to a solution of living yeast cells and water. The students add glucose to a mixture of yeast and water in Flask A. If a gas is released, the balloon on top of the flask will inflate. The students observe and record the appearance of the balloon at the beginning of the experiment, and again after 24 hours. The students did not include a control. Explain the importance of using a control in the experiment. Describe a control for this experiment. Be sure to include the specific parts of the setup. Compare the control to the original experimental setup. Flask

Scientific Notation Examples Ordinary decimal notation Scientific notation (normalized) 300 3×102 4,000 4×103 5,720,000,000 5.72×109 0.0000000061 6.1×10−9

Scientific Units Prefix Symbol Meaning Base Unit Multiplied by Factor tera-                T             trillion               1,000,000,000,000                    1012 giga-               g             billion                1,000,000,000                           109 mega-            M             million                 1,000,000                                 106 kilo-                k              thousand               1,000                                      103 hecto-              h             hundred                   100                                       102 deca-             da             ten                             10                                       101 single units, no prefix - Examples: meter, liter, gram 100 deci-               d              tenth                         0.1                                         10-1 centi-              c              hundredth               0.01                                        10-2 milli-               m              thousandth            0.001                                       10-3 micro-            u               millionth               0.000001                                  10-6 nano-               n               billionth           0.000000001                                10-9 pico-                p               trillionth         0.00000000001                             10-12

The Metric System The International System of Units (SI) is the modern form of the metric system and is generally a system of units of measurement devised around seven base units and the convenience of the number ten. Name Unit symbol Quantity metre m length kilogram kg mass second s time ampere A electric current kelvin K thermodynamic temperature candela cd luminous intensity mole mol amount of substance

pH Scale pH is a measure of the acidity or basicity of a solution. Acidity is the concentration of hydrogen ions (H+) Basicity is the concentration of hydroxyl ions (OH-) At pH = 7 (neutral) the concentration of OH- equals the concentration of H+ The equation for pH is: pH = -log[H+]

pH Scale pH [H+] [OH_] 14 1 10,000,000 13 1,000,000 12 100,000 11 10,000 10 1,000 9 100 8 7 6 5 4 3 2

pH Scale 1M NaOH 1M HCl

Acid Rain Acid rain is a rain or any other form of precipitation that is unusually acidic. Acid rain is caused by the emissions of ammonium, carbon, nitrogen, and sulfur which react with the water molecules in the atmosphere to produce acids.

Effect of pH on Living Systems Acid Rain can have harmful effects on plants, aquatic animals, and infrastructure through the process of wet deposition.

Effects of Acid Rain Sandstone figure in a castle in Germany, photographed in 1908 (left) and again in 1968 (right).

Outcome: Explain the role of carbohydrates by constructing and analyzing models of carbohydrates. Closing: Acidic solutions affect the health of plants. A neutral solution will cause more radish seeds to germinate than an acidic solution. Which of these hypotheses is better/more testable? Why? Cite at least two reasons for your opinion.