Design an experiment to demonstrate phototropism.

Object: To demonstrate phototropism

equipments: A black box, window with light source, a well watered potted plant.

Experiment: A wellwatered potted plant is placed inside a darkened black  box that is having a small window on one side. This is called as phototropic chamber. Window is remain closed for a day the plant shows normal growth.

Whereas if window is opened atwo days it will be found that shoot tip bends and grows towards light proving that it is positively phototropic.

in the given question, the partial pressure is calculated by using the ideal gas equation, that is, pv = nrt

here, p is pressure, v is volume = 25 l, n is number of moles = 0.0104 moles, r is gas constant = -0.0821 l.atm / mol.k

t is temperature = 273 k

p = nrt / v

p = (0.0104 mol × 0.0821 l.atm / mol.k × 273 k) / 25 l

= 0.0093 atm