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Mass Spectrometry
-A device that enables us to identify substances by working out their masses
-Has 5 Stages:
1. Vaporisation: Makes atoms easier to ionise
2. Ionisation: Atoms are blasted with a high energy electron gun which removes one electron from the outer shell of each atom Al(g) Al (g)…

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Ionisation energies

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Evidence for Energy Levels

First Ionisation Energies INCREASE across a PERIOD
1. Atomic Radius stays the same so electrons are being moved from the same shell Same level of shielding across the period
2. Nuclear charge increases due the increase of protons Increased pull from nucleus
First Ionisation Energies DECREASE…

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Melting and boiling points increase because there are more electrons being delocalised into the giant metallic structure Greater electrostatic forces of
attraction between positive ions and delocalised electrons
Group 4 Giant Covalent:
Silicon atoms are covalently bonded throughout in a giant covalent structure Difficult to melt or boil due to…

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Bonding:
Ionic Bonding:
-Happens between oppositely charged ions in a lattice which are attached to each other by strong electrostatic forces of attraction
-Have high melting and boiling points
-Conduct electricity when molten

Covalent Bonding:
-Shared pair of electrons
-Simple covalents have very weak intermolecular forces so have very low…

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Electronegativity:
-The ability/power of an atom to withdraw electron density from a covalent bond
-Increases across a period
-Decreases down a group
-N,O and F are the most electronegative elements
-Attraction causes uneven/asymmetrical distribution of electrons causing the more electronegative atom to develop a slightly negative charge and the other…

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1. Hydrogen Bonding

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2. Diapole-diapole Forces
3. Van Der Waal Forces

Diapole-diapole Attraction:
-Occurs when POLAR molecules (besides NOF) bond directly




Temporary Diapoles:
-Attraction caused using van der waal forces in NON-POLAR molecules
-Electrons in all molecules are in constant motion, this motion wobbles the electron cloud causing partially dense clouds resulting in…

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