A collection of pennies was investigated. 10.00% were found to have been minted in San Francisco with an average mass of 2.15 g and 90.00% we’re minted in in Philly with an average mass of 2.156 g. What was the average mass of pennies in this sample? Give the correct answer with the proper amount of significant figures

Chlorine and water react to form hydrogen chloride and oxygen, like this: 2cl2 (g) + 2h2o (g) → 4hcl (g) + o2 (g) also, a chemist finds that at a certain temperature the equilibrium mixture of chlorine, water, hydrogen chloride, and oxygen has the following composition: compound concentration at equilibrium cl2 0.55m h2o 0.57m hcl 0.53m o2 0.34m calculate the value of the equilibrium constant kc for this reaction. round your answer to 2 significant digits.