GIVING BRAINLIEST! What kinds of observations can you make that might indicate a chemical change is taking place?

Calculate the number of molecules present in 0.750 mol of mgo.

How do you know when a chemical reaction has occurred

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.