Question

Based on our retrospective view, Von Helmont's famous experiment on the growth of a willow tree mainly demonstrated that

• A. The tree increased in mass mainly by absorbing water
• B. The increase in the mass of the tree could not be accounted for by the consumption of soil
• C. Most of the increase in the mass of the tree was due to the uptake of oxygen
• D. Soil simply provides physical support for the tree without providing nutrients

Answer 1

The correct option is B The increase in the mass of the tree could not be accounted for by the consumption of soil

Basically, he performed the experiment using Willow tree seedling. He cultivated it under proper environment condition and with an adequate amount of water and on the final observation day, he noticed that the weight of the soil was nearly equal to the initial reading which he took before the start of the experiment, so this proves that the increase in mass is not because of soil consumption
So he wondered was all the weight came from and the only thing that he could think of is that the weight came from the water he added.
But he forgot about the weight that came from the carbon dioxide out of the air.
So, the correct answer is ' the increase in the mass of the tree could not be accounted for by the consumption of soil'