Calculate the number of milliliters of 0.591 M Ba(OH)2 required to precipitate all of the Fe 3 ions in 190 mL of 0.511 M FeBr3 solution as Fe(OH)3. The equation for the reaction is: 2FeBr3(aq) 3Ba(OH)2(aq) 2Fe(OH)3(s) 3BaBr2(aq) mL Ba(OH)2

While unproven, it uses facts to support part of a conclusion. it is still factual and has predictive power, however.

The total number of nucleons

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.