Bonding And Structure

Question 1

Explain ionic bonding

Answer 1

In order for an atom to have a complete outer shell it needs to gain or lose an electron.
Ionic compounds are created when atoms react trying to gain a full outer shell

Metal and non metal bonded

Question 2

What are the properties of an ionic compound (and why)

Answer 2

high melting and boiling point because the strong attraction between the ions needs a lot of energy to break

soluble in water because the charges on the ions attract the charges on the water molecules, which allows the ions to be pulled apart and surrounded by water

They conduct electricity when molten or dissolve because the ions are free to move around and carry electric charge

Question 3

What are simple molecular substances?

Answer 3

A few atoms held together by covalent bonds

Question 4

What is covalent bonding

Answer 4

When atoms bond because they want to have a full outer shell, they share electrons

Question 5

Diamond

Answer 5

Is a giant covalent structure that is an allotrope of carbon. each carbon in diamond is covalently bonded to four other carbon atoms. All of the outer shell electrons in carbon are involved in the bonding.

Question 6

Graphite

Answer 6

Graphite is a giant covalent structure that is an allotrope of carbon.

The carbon atoms are arranged in layers with each carbon atom bonded to three of the carbon atoms by strong covalent bonds.
Each atom has one electron and its out of shell that is not involved in bonding and is a free electron. layers have weak bonding between them.

Question 7

Uses of graphite

Answer 7

Conduct electricity because free electrons from each layer has delocalised electrons that carry charge

Used in pencils, electrodes, lubricants

Question 8

Uses of diamond

Answer 8

Diamond issues for drill, tips, jewelry, and a glass cutting

Question 9

Buckminsterfullerine

Answer 9

Carbon atoms form the shape of a ball with a carbon atom at each corner of the 20 hexagon and 12 pentagons

Used for a catalyst for lubricant nano tubes for strengthening and delivering drugs

Question 10

Carbon nanotubes

Answer 10

Conduct electricity because free moving electrons can travel quickly up the nano tube with nothing blocking their path

Question 11

Metallic bonding

Answer 11

The way that metal atoms bond to form a solid substance.
Outer shell electrons that move throughout the structure

The greater the number of free moving electrons, the greater the active forces in the metal this results in a high melting and boiling point

Question 12

Properties of metalically bonded things

Answer 12

Electrical conductivity free of electrons can move around and carry the electrical current

All metals are good conductive of heat free over electrons carry energy throughout the metal

Malleability metals are malleable as metal irons can slip past each other without difficulty

Question 13

Smart materials:
-thermochromic pigments

Answer 13

Special materials change the color to specific temperature. Examples include mugs T-shirt, and battery power indicators.

Question 14

Smart materials:
-polymer gel

Answer 14

Hydrogel are common examples. they can absorb or excel water as well as shrink/swell due to changes in pH uses, include artificial muscles filling for nappies, and in houses threatened by forest fires

Question 15

Smart materials:
-shape memory polymer

Answer 15

These are plastics that can regain their original shape when heated. when heated they can be stretched or deformed

When it cools, it remains in the molded shape if it shape is altered, it can be returned to its original shape by reheating used in gum, shields, helmets, and window frame ceiling

Question 16

Smart materials:
-shape memory alloy

Answer 16

Metal allies that gain their original shape when they are heated. Some allies have the amazing property of being elastic as well as being able to return to their original shape.
Use inspectable frame surgical plates for joining bones and thermostats

Question 17

Smart materials:
-photochromic glasses

Answer 17

These are special materials that change the color with light intensity, especially UV light. The light breaks up on the molecule, forming one with a different color.
Used in some clothing, but mostly use inspect lenses, allowing them darker with increased light