Iron becomes all the transition elements, figuring out the Valence electrons, the electrons that are most slightly right becomes a little bit hard to predict.

铁成为所有过渡元素，计算出价电子，最右边的电子变得有点难以预测。

Sometimes it does it otherwise but even for the other transition elements like say iron is not necessarily the case so these are the one, the only two electrons that are going to react.

有时它会以其他方式进行，但即使对于其他过渡元素，如铁，也不一定如此，所以这些是唯一的，唯一会发生反应的两个电子。