What does Elodea do to phenol red?
Phenol red turns yellow in a pH lower than 7, revealing in this case the presence of a carbon source. When a sprig of Elodea is added, the color will change back as the plant undergoes photosynthesis and uses the available carbon.
Why did the phenol red solution turn from yellow to red when the Elodea was added?
Why did the solution that contained Elodea maintained in light change from pale yellow to red? When the sprig of Elodea was added to the solution and placed in the light, the Elodea continued to photosynthesize. As a result, carbon dioxide was removed from the solution.
What color does phenol red turn in acidic solutions?
Phenol red is an example of a pH indicator, and it gives the yellow color in acidic solution and bright pink color in alkaline solution.
What color is the phenol red solution before blowing into it?
Answer and Explanation: Phenol red is an acid-base indicator that shows pink color in a basic solution and yellow color in an acidic solution.
Why did the solution eventually turn red?
carbon dioxide reacts with water to produc carbonic acid. As carbonic acid dissociates, the solution becomes more yellow, indicating a lower pH. When light is available and a plant is added, the solution returns to its original red color.
What was the purpose of using phenol red in the photosynthesis experiment?
Background. In this lab, you will use phenol red as an indicator to show whether CO2 is being consumed or produced in a reaction within plants. It is well known that in the presence of light plants perform photosynthesis.
What color is phenol red?
Phenol red, also known as phenolsulfonphthalein, is a pH indicator dye that exhibits a gradual transition from yellow to red over a pH range of 6.2 to 8.2 (Figure 2). Above 8.2 the dye turns a bright fuchsia color.
What colour is phenol red?
WHAT IS PHENOL RED? Phenol red is a water-soluble dye used as a pH indicator, changing from yellow to red over pH 6.6 to 8.0, and then turning a bright pink color above pH 8.1. As such, phenol red can be used as a pH indicator dye in various medical and cell biology tests.
What is the color of phenol red?
What does Elodea do in the dark?
In the dark, an elodea plant will turn a bromothymol blue solution yellow as it produces carbon dioxide as a product of respiration. An elodea plant exposed to light will turn yellow bromothymol blue back to the blue color as it uses carbon dioxide.
When exhaling into phenol red solution What causes the change in color and pH?
What color is between 650 and 740 nm? Why does the phenol red turn from red to a yellow/orange when exhaling into it? Because the CO2 from the exhale combines with the H2O in the solution to produce carbonic acid, lowering the PH.
Does phenol change color with no Elodea added?
4. Did you see a change in color of the phenol red test tube with no elodea added? Why or why not? No, because there was no plant to take in the carbon dioxide in the phenol red. 5. Does carbon fixation occur in humans?
Why did the solution that contained Elodea change from pale yellow to red?
Uptake of carbon dioxide in photosynthesis Answers to questions Why did the solution that contained Elodeamaintained in light change from pale yellow to red? When the sprig of Elodeawas added to the solution and placed in the light, the Elodeacontinued to photosynthesize. As a result, carbon dioxide was removed from the solution.
What does phenol red indicate in this experiment?
Phenol red is an indicator in this experiment. What did it indicate? The phenol red changes color because when we blow through the straw we are adding CO2 to it causing it to change a yellowish color. It indicated the carbon dioxide that plants need to go through photosynthesis.
What happens when the sprig of Elodea is placed in light?
When the sprig of Elodeawas added to the solution and placed in the light, the Elodeacontinued to photosynthesize. As a result, carbon dioxide was removed from the solution.