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What are the percent by mass of copper in penny lab

(04.05 hc) analyze the given diagram of the carbon cycle below. part 1: which compound does c represent? part 2: name a process that could release this compound into the air. part 3: explain how the elements that form it are conserved during the carbon cycle. use complete sentences to explain your answer. justify how this compound was created from a recycling of carbon in the carbon cycle. use complete sentences to explain your answer.

For the reaction i2(g)+br2(g)←−→2ibr(g), kc=280 at 150 ∘c. suppose that 0.450 mol ibr in a 2.00-l flask is allowed to reach equilibrium at 150 ∘c. what is the equilibrium concentration of 2ibr, i2, br2