What does the pondweed make when it does photosynthesis?
Red light is more easily used by the pond weed than most other colours. This process of making sugar and oxygen is called photosynthesis. Pond weed uses the carbon dioxide which is dissolved in the water it is in.
How do you measure the rate of photosynthesis of pondweed plant in this experiment?
Position the boiling tube so that the pondweed is 10 cm away from the light source. Allow the boiling tube to stand for five minutes. Count the number of bubbles emerging from the cut end of the stems in one minute. Repeat the count five times and record your results.
What is the gas produced by the pondweed in the light?
oxygen
The plants will release bubbles of oxygen – a product of photosynthesis – which can be counted. A lamp with an LED bulb is set up at different distances from the plant in a beaker of water: an LED bulb is best as this will not raise the temperature of the water.
What does the rate at which the bubbles are released indicate?
the rate of photosynthesis
The number of bubbles released in a given time can be counted as a measure of the rate of photosynthesis. The apparatus in the diagram shows how the volume of oxygen produced in a given time may be measured instead.
How do you calculate rate of photosynthesis?
They varied the distance of the plant from the light source. In the table below, the Rate of photosynthesis = Number of bubbles produced per minute….Scientific calculations.
| Distance | Rate |
|---|---|
| 10 cm | 120 |
| 15 cm | 54 |
| 20 cm | 30 |
| 25 cm | 17 |
What is the dependent variable in the photosynthesis experiment?
Dependant variable – the number of oxygen bubbles given off (the rate of photosynthesis). Controlled variables – the size of the pondweed, the volume of water used and its temperature.
When pondweed was left in a tube of the indicator for a day the solution went purple explain why?
Answer: When pondweed left in a tube of the indicator for a day, the solution went purple. This indicates that the pondweed is in low concentrations of carbon dioxide.
How does temperature affect the rate of photosynthesis in pondweed?
When the temperature rises the rate of photosynthesis rises also. There is an optimum temperature at which the rate of photosynthesis is maximum. Beyond this temperature, the reaction quickly comes to a halt. Place a pond weed Elodea upside in a test tube containing water at 25°C.
What temperature will result in the highest rate of photosynthesis?
At medium temperatures, between 50 and 68 degrees Fahrenheit, or 10 and 20 degrees Celsius, the photosynthetic enzymes work at their optimum levels, so photosynthesis rates gauge high. Depending on the particular plant in question, set the greenhouse thermostat to a temperature within this range for best results.
How do you calculate the number of bubbles produced?
They varied the distance of the plant from the light source. In the table below, the rate of photosynthesis = number of bubbles produced per minute….Results.
| Distance | Rate |
|---|---|
| 10 cm | 120 |
| 15 cm | 54 |
| 20 cm | 30 |
| 25 cm | 17 |
What does the color change from green to yellow indicate about the concentration of CO2 in the solution?
When carbon dioxide is added to the solution, it creates carbonic acid, lowering the pH of the solution. BMB is blue when the pH is greater than 7.6, green when the pH is between 6-7.6, and yellow when the pH is less than 6.
Why does the rate of photosynthesis lead to a colour change in the indicator solution?
In bright light, the rate of photosynthesis is greater than rate of respiration. So, leaf takes in CO2 from the air in the test tube. This reduces the CO2 inside the test tube and the colour of hydrogen-carbonate indicator solution changes from orange to purple as CO2 is taken away form the solution.
How temperature affects the rate of photosynthesis experiment results?
As with other chemical reactions, the rate of photosynthesis increases as the temperature rises. Photosynthesis is controlled by enzymes , which become denatured if the temperature is too high. As a result, the rate of photosynthesis reaches its maximum at an optimum temperature, then decreases.
What is the effect of high and low temperature on rate of photosynthesis?
Higher the temperature, greater the rate of photosynthesis. This is because photosynthesis is a chemical reaction and most of the chemical reactions are accelerated with temperature. But, in the case of photosynthesis, a temperature of above 40 °C decreases the rate of photosynthesis.
How do you calculate rate of reaction from a table?
From a Table. To determine the rate law from a table, you must mathematically calculate how differences in molar concentrations of reactants affect the reaction rate to figure out the order of each reactant. Then, plug in values of the reaction rate and reactant concentrations to find the specific rate constant.