Question

A student placed a sprig of green water plant under a funnel in a glass vessel full of water and then placed a test tube full of water mouth-downward over the stem of the funnel. After the setup had been exposed to sunlight for several hours, the student tested a gas that had collected in the test tube and concluded that the plant had produced oxygen. The results of this experiment could have been interpreted more satisfactorily if

Answer 1

Answer:

Explanation:

ill a sink with water and set the beaker in it. Put some elodea in the beaker and cover it with the funnel.

Now submerge the test tube in the water so that there is no air inside it. While holding it under the water, carefully place it over the neck of the funnel. Don’t let its mouth break the surface of the water.

Lift the whole apparatus out of the water. You can tip a little water out of the jar so it won’t spill. Set the jar on a sunny windowsill. As soon as the elodea begins to photosynthesize, you will see tiny bubbles appearing on its leaves and then floating upwards into the test tube. These bubbles are oxygen produced by photosynthesis!

Leave the jar on the windowsill for several hours. The rate of photosynthesis will vary depending on the intensity of the sunlight and other factors, but slowly the oxygen will collect in the test tube.

The results of this experiment could have been interpreted more satisfactorily if, he could have used a match to light the wooden splint, then gently blow it out again and then immediately lift the test tube straight up and insert the splint up into it, without touching it to the sides of the test tube. If the splint should glow brightly, or even burst back into flame! This is proof that the gas you collected is oxygen, which is flammable.

Normally  the oxygen produced by photosynthesis cant be seen, but when it is produced underwater it appears as bubbles in the water.

It floats up through the funnel and displace the water in the test tube. Fire needs oxygen to burn, so when you insert the splint, the pure oxygen in the test tube causes it to glow brighter or produce a flame.