Beryillium's 1st ionisation energy is 900...
while Barium's is 500. Why are they different?
2007-01-16 22:19:56 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
Because Be has fewer electron shells (2) than Ba (6) its electrons are much closer to the nucleus of the atom. To remove an electron from an atom (ionisation) the force of attraction between the electron and the nucleus must be overcome. Closer to the nucleus = greater attraction = more force required for ionisation.
btw Be has 4 protons! and Ba has 2 valence electrons!!
2007-01-16 22:53:41 · answer #1 · answered by Anonymous · 0⤊ 0⤋
2 Reasons.
1. Barium only has one outermost electron. That makes it much easier to donate that Beryillium (or any other group II elements), which have 2 to get rid of.
2. Barium's lone valence electron is much further away than Beryillium. As distance increase the electrostatic forces of attraction from the nucleus to electrons gets weaker, so electron is more readily donated. This is why as we go down group I and II metals reactivity increases.
2007-01-17 06:53:41 · answer #2 · answered by koala_paradise 3 · 0⤊ 0⤋
Coz Be has 2 electrons in its valence shell and hence two protons. Be's valence shell is its second one. Ba also has 2 electrons in its valence shell situated futher away from the nucleus of its atom. Ba's valence shell is its 6th
2007-01-17 06:27:02 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Lower shielding in Be.
2007-01-17 06:57:38 · answer #4 · answered by ag_iitkgp 7 · 0⤊ 0⤋