Water and phosphorus with a total mass of 200 grams are added to a flask like the one below and then the flask is sealed with a rubber stopper. The flask is then heated up so that a reaction occurs but no gas from the reaction escapes the flask. How much mass would you
expect to be in the flask after the reaction occurs? Drag and drop your answer into the white box.
more than 200 grams
200 grams
400 grams
less than 200 grams