Structure and bonding Flashcards
Why are pure metals softer?
The layers of metal ions can slide over each other
What is an alloy?
A metal that contains at least one other type of element often a metal.
What are alloys strong?
The extra elements will be a different size which disrupts the regular layers.
What is a state change from a solid to gas or gas to solid called?
Sublimed
What are vertical columns called in the periodic table?
Groups
Why do elements bond?
So they can gain a full outer shell
What is an ion?
When an element gains electrons to have a full outer shell
What is a metal?
Only metal
What is a simple covalent molecule?
non metal bonded to another non-metal
What is a giant covalent molecule?
Non-metals (silicon dioxide, diamond, graphite)
What is covalent bonding?
Where the pairs of electrons in the outer shell are shared.
Covalent bonding occurs with what material?
Non-metals
What are properties of covalent compounds?
.Low melting/boiling points
.Do not conduct electricity
What happens when a covalent substance melts/boil?
The weak intermolecular forces between the molecules are broken
Why do simple covalent molecules not conduct electricity?
There are no charged particles
What are diatomic elements?
Elements that go around in pairs.
What group in the periodic table are diatomic?
7 (the halogensj
What is Ionic bonding?
The electrons in the outer shell of the metal atom are transferred.
Ionic bonding happens with what 2 type of materials?
Metals and non metals
What happens to the metal after ionic bonding.
Looses atoms and becomes positively charged ions.
What happens to the non-metal after ionic bonding?
Negatively charged ions
What are properties of ionic compounds?
.Sharp edges
.High melting
.Soluble
.Conducts when dissolved or molten
What is the ionic formulae?
Positive ions = negative ion charges
Why do ionic compounds have high melting points?
They are in a ionic lattis Strong electrostatic forces of attraction between ions. A lot of energy is needed to brake.
