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Ion
Formed when an atom loses or gains electrons
Ionic Compound
Bonding of a metal and non-metal atom bonding
Molecule
2 or more atoms chemically joined together
How do simple molecules form?
Bu covalent bonding between non-metal bonding
What do ionic substances look like?
Crystal-cubic shape
Properties of ionic substances?
High boiling point
Hight melting point
Conducts electricity
Why can ionic substances conduct electricity in the molten state?
Ions can carry charge throughout the substance
Why do ionic substances look like this?
Regular 3D ionic lattice with strong bonds between them
How does a Mg atom become a Mg^2+ ion?
Loses 2 electrons
How does a Cl atom become a Cl- ion?
Gains 1 electron
How is NaCl formed?
Na- Loses 1 electron (Na+)
Cl- Gains 1 electron (Cl-)
What is the structure of an ionic compound?
Giant 3D lattice structure held together by strong oppositely charged ions
Why do ionic structures not conduct electricity in the solid state?
Fixed electrons
Why do ionic substances have high melting and boiling points?
Strong electrostatic forces that require a large amount of energy to break
What is the structure of a simple covalent molecule?
Strong covalent bonds between non-metal atoms with weak intermolecular forces between the molecules
What are the simple covalent molecules on the spec?
Chlorine (Cl2)
Methane (CH4)
Oxygen (O2)
Ammonia (NH3)
Nitrogen (N2)
Hydrogen (H2)
Hydrogen Chloride (HCl)
Water (H2O)
What do simple covalent substances look like?
Weak forces between molecules
What are the properties of simple covalent substances?
Low melting point
Don’t conduct electricity
Why do simple covalent substances have low melting and boiling points?
Weak forces that require little energy to break
What are the giant covalent substances on the spec?
Diamond
Graphite
Silicon dioxide
Fullerenes
Graphene
Polymers
What is the structure of graphite?
Layers of hexagonal rings held together by weak intermolecular forces.
1 carbon atom bonded to 3 others
Why is graphite slippery?
Weak forces are easily broken
Why does graphite have a high melting point?
Strong covalent bonds that require a lot of energy to break
Why does graphite conduct electricity?
Free electron from each carbon atom that can carry charge throughout the structure
What are fullerenes?
Carbon atoms in the shape of cages/ balls/ tubes
What is the structure of diamond?
Carbon atoms held together by strong covalent bonds between the atoms. Each atom is bonded to 4 others in a giant lattice structure
What is the structure of silicon dioxide?
Carbon atoms held together by strong covalent bonds between the atoms. Each atom is bonded to 4 others in a giant lattice structure
Why is diamond hard?
Strong bonds between the atoms meaning lots of energy is needed to break and there is a lot of bonds that need to be broken
Why does diamond have a high melting point?
Strong bonds between the atoms meaning lots of energy is needed to break and there is a lot of bonds that need to be broken
Why does silicon dioxide have a high melting point?
Strong bonds between the atoms meaning lots of energy is needed to break and there is a lot of bonds that need to be broken
Why does diamond NOT conduct electricity?
No free electrons/ ions to carry charge
Why does silicon dioxide NOT conduct electricity?
No free electrons/ ions to carry charge
What is the structure of a metal?
Lattice of metal ions (+) surrounded by a sea of charged electrons (-)
Why are metals malleable?
Layers of atoms can slide over each other
Why do metals have a high melting point?
Electrostatic forces between ions (+) and electrons (-) are strong
What are alloys?
Made from a mixture of elements (at least 1 is a metal)
Why are metals usually harder than the pure metal itself?
Different atoms have different sizes that disrupts the structure and makes it more difficult for the layers to slide over each other
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