AS 91390 Thermochemical Principles

Question	Answer
First Ionisation Energy (FIE)	A measure of the minimum energy reguired to remove the most loosely held electron from each atom in a mole of the element in its gaseous state.
Why does FIE decrease going down a group?	The electron being lost is futher away from the nucleus (therefore weaker elestrostatic forces). If elements being compared are in different period, there is also more electron shielding (weakens electrostatic attraction due to electron-electron repulsion between energy shells), so it is not held as tightly.
Why does FIE increase across a period?	The number of protons increase and thus electrons are added in the same energy level and the effective nuclear charge (e.n.c.) acting on the outermost electron is stronger
Metalic Bonds	Electrostatic attraction between the lattice of (+ve) metal nuclei and surrounding delocalised electrons (-ve)
Malleable	Can be bent without shattering. Electrons can slide past the nuclei and one another.
Ductile	Can be bent without shattering. Electrons can slide past the nuclei and one another.
Electrically Conductive	In solid/liquid state. Sea of freely moving charged protons (electrons).
Ionic Bonds	When metal and non-metals react

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	Created by lauren calvert over 6 years ago