C3-structure and Bonding

Question 1

What are the the three states of matter called?

Answer 1

Solids,liquids and gases

Question 2

What is the position of the particles in each of the three states of matter?

Answer 2

Solid-particle are packed closely together and vibrate around fixed positions

Liquid-the particles are close together but can slip and slide over each other in random motion.

Gas- the particles in a gas have, on average, lots of space between them and zoom around randomly

Question 3

In melting and boiling how is energy transferred

How is energy transferred in freezing and condensing?

Answer 3

Energy is transferred from the surroundings to the substance

Energy is transferred from the substance to the surroundings

Question 4

How do elements react together to form compounds

Answer 4

By gaining or loosing or sharing electrons

Question 5

What is ionic bonding?

Answer 5

Where ionic compounds are held together by strong forces of attraction between their oppositely charged ions.

Question 6

Why do ionic compounds have high melting and boiling points?

Answer 6

It takes a lot of energy to break the many strong ionic bonds, operating in all directions that hold a giant ionic lattice together. They are also solids at room temperature.

Question 7

Why can ionic compounds not conducted electricity when they are solids?

Answer 7

Because the ions cannot move. They are locked in place by the strong electrostatic forces of attraction.

Question 8

Ionic compounds can conduct electricity when they are melted or dissolved in water. Why is this?

Answer 8

The ions can now move and carry the charge due to high temperature provides enough energy to break the bonds-molten and water molecules separate ions from the lattice ions are free to move around within the solution-ionic compound in solution

Question 9

When are covalent bonds formed?

Answer 9

When atoms of non-metals share pairs of electrons with each other.
Each shared pair of electrons is a covalent bond
Many substances containing covalent bonds consist of simple molecules jug some have giant covalent structures

Question 10

What do many substances containing covalent bonds consist of?

Answer 10

Simple molecules but some have giant covalent structures

Question 11

Do substances made up of simple molecules have low melting and boiling points?

Answer 11

Yes

Question 12

Why do substances made of simple molecules have low melting and boiling points.

Answer 12

The forces between the simple molecules are weak.

Question 13

Why can simple molecules not conduct electricity?

Answer 13

Because they have no overall charge, so they cannot carry electrical charge.

Question 14

Why is graphite soft and slippery

Answer 14

Graphite contains giant layers of covalently bonded carbon atoms. However there are no covalent bonds between the layers.this means they can slide over each other, making graphite soft and slippery.

Question 15

Why can graphite conduct electricity and thermal energy?

Answer 15

Because the delocalised electrons can move along its layers.

Question 16

What is the general name for all these hollow-shaped molecules of carbon

Answer 16

Fullerenes which can form large cage like structures and tubes based on hexagonal rings of carbon atoms

Question 17

What are uses for fullerenes?

Answer 17

A transport mechanism for drugs to specific sites of the body

Catalysts

And as a reinforcement for composite materials

Question 18

Graphene is a single layer of graphite and so is just one atom thick. What are its properties

Answer 18

Excellent electrical conductivity will help create new developments in the electronics industry in the future

Question 19

How are atoms in metals arranged?

Answer 19

They are closely packed together and arranged in regular layers

Question 20

What is metallic bonding?

Answer 20

The bond produced due to the combination of electrostatic force of attraction between the negative electrons and the positive nucleus of metal atoms

Question 21

Why can the metals be bent and shaped?

Answer 21

Because the layers of atoms in a giant metallic structure can slide over each other

Question 22

Why are alloys harder than pure metals

Answer 22

Because the regular layers in a pure metal are distorted by atoms of different sizes in an alloy

Question 23

What is nano-science

Answer 23

The study of small particles between 1 and 100 nanomètres in size

Question 24

Nanoparticules may result in smaller quantities of materials. Give an example of what it could be used for?

Answer 24

Catalysts, being needed for industrial processes.

Question 25

What can nanoparticules be used for?

Answer 25

Medicines 
Si screams 
Deodorants 
Electronics 
Cosmetics 
Catalysts

Question 26

What are the risks of nanoparticules?

Answer 26

Nanoparticles can be absorbed into the body and enter our cells. And no-one knows the potential long-terms effects of this