T3+Daniel

1) Number Z || First Ionisation Energy (kJ/mol) || 2)
 * Task 3**
 * Element || Proton
 * Li || 3 || 520 ||
 * Na || 11 || 496 ||
 * K || 19 || 419 ||
 * Rb || 37 || 403 ||
 * Cs || 55 || 376 ||

3) First ionisation energies decrease down the group because as we go down the group, the number of shells increase as does the distance between the valence electrons and the nucleus. Although the number of protons increases down the group, attraction between the nucleus and valence electrons decreases due to the shielding effect of more electrons in filled inner shells and also due to the increased distance between them. 4) 5) Increasing 6) There is an increase in reactivity in the Group 1 metals (Li, Na, K, Rb, Cs) as you go down the group in terms of the fall in ionisation energy. Whatever these metals react with, they form positive ions in the process, and so the lower the ionisation energy, the more easily those ions will form. 7) Group 2 will show similar trends to that of group 1 elements because as you go down the group, the first ionisation and electronegativity decreases. This is because as you go down group 2, the atomic radius of the elements increases just like group 1. 8) Number Z || First Ionisation energy (kJ/mol) ||
 * Element || Proton
 * Li || 3 || 520 ||
 * Be || 4 || 900 ||
 * B || 5 || 801 ||
 * C || 6 || 1806 ||
 * N || 7 || 1402 ||
 * O || 8 || 1314 ||
 * F || 9 || 1681 ||
 * Ne || 10 || 2081 ||

9)  10) Because as the nuclear charge increases, the attraction between the nucleus and the electrons increases and it requires more energy to remove the outermost electron and that means there is a higher ionization energy. As you go across the periodic table, nuclear charge is the most important consideration. So, going across the periodic table, there should be an increase in ionization energy because of the increasing nuclear charge.  11) Number Z || Electronegativity (Pauling) || 12)
 * Element || Proton
 * Li || 3 || 0.98 ||
 * Be || 4 || 1.57 ||
 * `B || 5 || 2.04 ||
 * C || 6 || 2.55 ||
 * N || 7 || 3.04 ||
 * O || 8 || 3.44 ||
 * F || 9 || 3.98 ||
 * Ne || 10 || 0 ||

13) Electronegativity increases across a period because the number of charges on the nucleus increases. This attracts the bonding pair of electrons more strongly. 14) The reactivity across the period is in the form of a parabola.  For the metals, eg. period 3 Potassium, Calcium and Aluminium, reactivity decreases since while potassium needs to lose one electron to achieve stability, aluminium needs to lose three. For non-metals, on the other hand, taking Carbon, Nitrogen, Oxygen and Fluorine (excluding noble gases) the opposite is true. While carbon needs energy to form 4 covalent bonds, or to gain four electrons, fluorine only needs to gain one electron or form one covalent bond. Thus reactivity increases along the period for non metals. 15) Because Neon is a noble gas. That means it has a full outer shell and does not need to bond with any other atom to become stable. Hence, the electronegativity level is zero.