A video gaining popularity on social media purports to show a self-contained, self-sustaining biosphere, conveniently available for purchase. The device shown in the video consists of an airtight, mirrored bottle, containing some water, a houseplant you don’t recognize, a waterproof light bulb, and an electrical generator powered by a weight and pulley assembly. The video explains, via a colorful animation, that the plant, when exposed to light, lifts the weight; when the light shuts off, the plant releases the weight, which powers the light bulb, reviving the plant, starting the cycle over again. The narrator claims that this process is so efficient; the bottle actually feels warm to the touch despite receiving no additional energy. You know this is clearly impossible, but what facts

Question

support your assertion?

a. The only part of this system that would not work as described is the gravity generator; plants cannot exert enough force to lift a weight into the air as described.
b. The problem with this device lies with the light bulb; even if the apparatus functions as described, plants cannot photosynthesize artificially-produced light.
c. All metabolic processes lose energy to entropy as waste heat; the fact that the bottle is warm to the touch indicates it is losing energy that is not being replaced.
d. Corrosion is an exergonic reaction that occurs spontaneously; in an airtight bottle with a source of water, any metal parts will rust immediately, halting the device.

Answer 1

c. All metabolic processes lose energy to entropy as waste heat; the fact that the bottle is warm to the touch indicates it is losing energy that is not being replaced.