While respiration plants produce carbon dioxide using oxygen.
Test tubes, test tube holder, cork, cork drills, filter paper, scissors, dropper, calcareous water, phenolphthalein indicator, potato, calcareous, apple, mushroom
Cut 7*15 cm stripes of the filter paper crook them alongside. Cut bars from the substances of the same size. Drip 10 drops of calcareous water to each test tube and drip 2 drops of the indicator and put the filter paper into and cork them. Turn the test tubes sidelong until the filter paper absorbs the liquid then put into them from each substance and the 5th test tube is the control. Measure the time until the filter papers lose their colours.
3 test tube, 0,1 w%, 1 w%, 2 w% Sodium bicarbonate tincture, 3 water plants of the same kind
Fill the test tubes with the tinctures then put a plant into each tube. Watch the formation of the bubbles and if necessary put the plants back into the tubes.