UNIT 1 - BONDING Flashcards
WHAT ARE IONIC BONDS ?
Bonds between metals and non-metals
HOW ARE IONIC BONDS FORMED ?
METALS LOSE ELECTRONS AND NON-METALS LOSE ELECTRONS IN ORDER TO ACHIEVE A FULL OUTER SHELL OF ELECTRONS
WHAT ARE THE PROPERTIES OF IONIC COMPOUNDS ?
HIGH MELTING AND BOILING POINT
BRITTLE
CONDUCT WHEN MOLTEN
SOLUBLE IN WATER
WHY DO IONIC COMPOUNDS HAVE HIGH MELTING AND BOILING POINTS ?
A lot of heat energy is required to break the strong ionic bonds / electrostatic forces between ions
WHY ARE IONIC COMPOUNDS BRITTLE ?
When force is applied to an ionic crystal, the layers shift bringing ions of the same charge together they repel causing the crystal to shatter
WHY DO IONIC COMPOUNDS CONDUCT WHEN MOLTEN ?
In a solid ions cannot move so cannot carry electricity
When molten or dissolved ions move to carry current
WHY ARE IONIC COMPOUNDS SOLUBLE IN WATER ?
Water molecules are slightly charged and so are able to break apart ions in ionic lattice
HOW ARE COVALENT BONDS FORMED ?
Electrons are shared between non-metals to complete a full outer shell
WHAT IS BONDED IN A COVALENT BOND ?
Non-metals
PROPERTIES OF COVALENT BONDS ?
LOW MELTING AND BOILING POINT
POOR CONDUCTORS
WHY DO COVALENT BONDS HAVE A LOW MELTING AND BOILING POINT ?
Covalent bonds are strong but the intermolecular forces are weak, meaning they can be broken with little heat energy
WHY ARE COVALENT COMPOUNDS POOR CONDUCTORS ?
They cannot conduct as they have no mobile charged particles
WHAT IS THE STRUCTURE OF DIAMOND ?
4 (c-c) bonds, no free electrons
WHAT ARE THE PROPERTIES OF DIAMOND ?
HIGH MELTING AND BOILING POINT
STRONG
ELECTRIC INSULATOR
WHY DOES DIAMOND HAVE A HIGH MELTING AND BOILING POINT ?
Each carbon forms 4 (c-c) bonds with strong covalent bonds which require high energy to break
NAME THREE CARBON ALLOTROPES
CARBON
GRAPHITE
GRAPHENE