The fe2+(aq) solution described in part a was produced by dissolving 4.05 g of ore in acid. what was the percentage of fe by mass in this ore sample?

We can't solve this problem with that data.

Explanation:

Hi! Let's solve this!

To calculate the mass percentage, use (mass of Fe / total mass of ore) * 100

In this case we have the mass of Faith but the exercise does not have enough information to calculate the percentage.

We can't solve this problem with that data.

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.