How does pH level affect the photosynthesis rate in plants? Tessa Sammy Emily Tom These pictures in the presentation do not belong to us In the notes section are the websites we obtained them from

Introduction  Photosynthesis is the process that plants use to make food and energy for themselves  It converts sunlight into electrical energy and then chemical energy  The plant takes in carbon dioxide, water, and sunlight and produces sugar and oxygen  Plants are the only organisms that can produce their own energy using photosynthesis  We designed an experiment to see if the pH level will affect the photosynthesis rate in the plant.  Our question was: how does pH level affect the photosynthesis rate in plants?  Our hypothesis was: if a plant is in a solution of water with a pH level lower than 7, then the rate of photosynthesis will slow.

Procedure  Procedure 1.Fill up a beaker with 500 ml of water. 2.Put 0.8 grams of baking soda in the water and stir it. 3.Pour the water into 3 separate 80 ml beakers. 4.Label the beakers 1, 2, and 3. 5.In Beaker 1 put in 50 drops of hydrochloric acid to change the pH level to 3. 6.In Beaker 2 put in 50 drops of potassium hydroxide to change the pH level to Don't add anything to Beaker 3. 8.Meanwhile use the hole punch to cut out 9 circles of swiss chard being careful not to punch out the circles with bigger veins. 9.Fill up the syringe with water from Beaker 1 and 3 circles of swiss chard. !0.Putting your thumb over the top of the syringe, pull down on it to get air bubbles, then push up until the air bubbles are gone. Do this until all the air is out and the circles sink to the bottom. 11.Put the water and the plant circles from the syringe back into Beaker Place Beaker 1 under a light and time how long it takes each circle to rise to the surface. 13.Record your data. 14.Repeat steps 9-13 with Beakers 2 and 3.

Materials  Materials ml beaker ml beakers -Safety goggles -Gloves -Hydrochloric acid -Potassium hydroxide -1 Swiss chard leaf -Hole punch -Syringe -Water

Data and Results

Conclusion  We discovered that our experiment did not support our hypothesis.  We thought that a lower pH level could cause the photosynthesis rate to slow but a lower pH level actually caused the photosynthesis rate to speed up.  A pH level of 3 had an average photosynthesis rate of 92.7 mm/s while a pH level of 10 had an average photosynthesis rate of mm/s.  A regular pH level of 7 had an average photosynthesis rate of mm/s.  This means that the pH 3 has a faster photosynthesis rate than pH 10 by mm/s.  We never expected that a pH level of 3 would cause a faster photosynthesis rate than a pH level of 10, but it turned out to be faster than pH 10 and faster than a pH of 7 which is normal for plants.