A sample of ferric oxide (Fe2O3, density 5.24 g/mL) obtained from ignition of a gravimetric precipitate weighed 0.296 1 g in the atmosphere. What is the true mass in vacuum?
3.5 Periodic variations in element properties continued Trends in successive ionization energy Increases left to right and top to bottom The huge jump in ionization energy correspond to when it goes from removing valence electrons to removing core electron Example problems Where is the jump in ionization energy for Li 1. First let’s write the electron configuration. 1 2¹ 2. Now let’s identify the valence and core electrons. Valence electrons are in the outermost energy level which in this case is 2. So, we have 1 valence electron. Core electrons are all other electrons, that aren’t in the outermost energy level. So, we have 2 core electrons.