Photosynthesis experiments

1. A ________ variable is one you keep the same to help make a test fair and valid.
2. Soda lime is a chemical that _______ carbon dioxide from the air so can be used to see the effect of reducing the concentration of carbon dioxide on the rate of photosynthesis
7. _________ solution can be used to test a leaf for starch (if starch is present it will go blue-black)
8. Rate of photosynthesis can be measured by counting the number of oxygen _________ produced by a water plant.
9. In this experiment, a beaker of water is often put between the light and the plant to try and absorb ______ from the light.
10. The __________ variable is the one you plan to change to see what effect it has.
14. _________ dissolves the chlorophyll in a leaf to turn it white so you can see colour changes better
15. Oxygen gas can ________ a glowing splint.

1. Adding sodium hydrogen carbonate to water can increase the amount of _________ __________ dissolved in the water (e.g.in the experiment below to see the effect of changing this on the rate of photosynthesis)
3. Ethanol is very __________ and can’t be near flames.
4. ________ leaves can be used to investigate the effect of having chlorophyll on photosynthesis
5. The __________ variable is the one you measure to see if it has been affected.
6. Result can be made more reliable by ________ the experiment and seeing if the results are similar.
11. You can _________ a leaf by putting it in the dark for at least 24 hours. The plants will then use up their starch stores (starch will be turned to glucose and used by the plant e.g. for respiration).
12. ________ a leaf will kill it and stop any chemical reactions taking place. Enzymes will be denatured.
13. Using _ _ _ lights is another way to change light intensity without changing heat too much.