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Mini-Project II - The Snail That Would Not Die Introduction: Watch this video on Carbon-dating: https://tinyurl.com/Math238 Video1 In this project we are going to explore some ideas surrounding UPPER TROPOSPHERE Carbon-14. We know that Carbon-14 decays exponentially so it's quantity in a closed system can be modeled by the differential PHOTOSYNTHESIS equation: dC = KC CARBONATE OCEAN dt If C = kg of Carbon-14 in the system and / is given in years. (Illustration by Jayne Doucette, Woods Hole Oceanographic Institution) Knowing the half-life of C-14 is 5730 years calculate & and include units. k = Note that this model works for a closed system. For example a dead wooly-mammoth is a closed system and this model would work well because nothing is leaving or entering the wooly-mammoth carcass. It's just sitting there slowly decaying, or frozen in the ice. Side story read this article about wooly mammoth meat: https://tinyurl.com/Math238Article1 Carbon-14 has a natural abundance of 1 part per trillion or 0.0000000001%. Meaning for every trillion normal Carbon-12 atoms there is 1 Carbon-14 atom. It's quite rare. If a buried tree was found to contain 0.2 parts per trillion of Carbon-14 how old is it? Age of tree = But the atmosphere is not a closed system. The reason is, that Nitrogen-14 is being converted into Carbon-14 at some rate, so the quantity of Carbon-14 in the atmosphere must be modeled as: dc dt = kC + R The atmosphere contains 5.137 x 1018 kg of carbon. How much Carbon-14 is in the atmosphere in kg? Mass of C-14 =Knowing the amount of Carbon-14 in the atmosphere is constant with time calculate R, the rate at which Carbon-14 is produced in the upper atmosphere, include units. Some \"Creation Scientists\" say that Carbon-dating is an invalid means of determining the age of an object. Their reasoning is that some living mussels and snails in a lake in Nevada were Carbon-dated to be 27,000 years old. Therefore the method invalid. The lake is in an area where water percolales through limestone. Why might the living snail be carbon-dated to be 27,000 years old