if you were to repeat Van Helmont’s experiment, how would you improve it and what table would you construct for recording your result.
Answers
Answer:
Van Helmont famously planted the shoot of a willow tree into a container of soil, watered the soil for five years and concluded 'the 164 pounds of wood, bark, and root arose from the water alone' (Harvey, 1929, p. 543; McCall, 1931, p. 45).
'Helmont's conclusion was in error because he did not know that plants absorb mineral elements from the soil and carbon dioxide from the air' (Hershey, 1991, p. 458).
Two questions:
Firstly, would van Helmond have been right if he had concluded that the 164 pounds of wood, bark, and root arose from water, from mineral elements in the soil, and from the carbon dioxide in the air? If not, why not?
Secondly, the average weight of an adult in England is 78.1kg (NHS Digital, 2016). Would it be true to say that all the tissue in an adult male has arisen from the food and air that the adult has taken into their body during their lifetime? If not, why not.