Which substance must be added at Y to complete this reaction?

In which environment would primary succession occur? a forest with a few remaining trees after a recent wildfire an area of exposed rock after a glacier melts away beach that is exposed to the air at low tide an abandoned baseball field in a small town

0.09 moles of sodium sulfate in 12 ml of solution

What does the mass of 0.7891 mol of ferric oxide (fe2o3)