Bonding

Question 1

What is Ionic Bonding

Answer 1

transfer of electrons

Question 2

What is Covalent Bonding

Answer 2

sharing electrons

Question 3

Name two features of a simple molecular structure

Answer 3

Low boiling/melting point, poor conductor

Question 4

Name two features of a giant metallic structure

Answer 4

High boiling/melting point, good conductor

Question 5

Name two features of a giant covalent structure

Answer 5

High boiling/melting point, poor conductor

Question 6

Name two features of a giant ionic structure

Answer 6

High boiling/melting point, conducts when molten

Question 7

Simple Molecular Structures have _____ intermolecular forces

Answer 7

weak

Question 8

Simple molecular structures have no free ions. True or False?

Answer 8

True

Question 9

Simple molecular structures have free ions. True or False?

Answer 9

False

Question 10

Giant Covalent Structures have _____ intermolecular forces

Answer 10

Strong

Question 11

Giant Covalent Structures don’t conduct except for molten Graphite. True or False?

Answer 11

True

Question 12

Giant Covalent Structures are good conductors. True or False?

Answer 12

False

Question 13

Which structure can be formed to have layers so that they can slide over eachother and can be used to make pencil leads?

Answer 13

Giant Covalent

Question 14

Name three features of a Giant Metallic Structure

Answer 14

Strong intermolecular forces between positive and negative ions, free electrons allowing it to conduct well, layered structure to allow the metal to be bent and shaped.

Question 15

Why are Alloys harder than pure metals?

Answer 15

The sizes of the atoms in alloys are mismatched so the layers do not slide so easily over each other.

Question 16

Covalent compounds have a covalent lattice structure and conduct when melted or dissolved. True or False?

Answer 16

False

Question 17

Ionic compounds have an Ionic lattice structure and conduct when melted or dissolved. True or False?

Answer 17

True

Question 18

What groups of the periodic table are ions often from?

Answer 18

1, 2, 6 & 7

Question 19

What varieties do Covalent substances come in?

Answer 19

simple molecular and giant covalent

Question 20

Do simple molecular structures have free ions?

Answer 20

No

Question 21

What are Ions?

Answer 21

Ions are electrically charged particles formed when atoms lose or gain electrons. This loss or gain leaves a complete highest energy level, so the electronic structure of an ion is the same as that of a noble gas - such as a helium, neon or argon.

Question 22

What type/types of atoms does Ionic bonding happen between?

Answer 22

A Metal and a Non-Metal.

Question 23

Which atom becomes Positively charged and which atom becomes Negatively charged in Ionic bonding?

Answer 23

Metal atoms lose the electron, or electrons, in their highest energy level and become positively charged ions
Non-metal atoms gain an electron, or electrons, from another atom to become negatively charged ions

Question 24

How do you know what number of charges an ion has?

Answer 24

The charge number is the number of electrons the ion has gained or lost. The positivty/negativity of that charge depends on whether those atoms where gained or lost.

Question 25

An atom loses an electron in Ionic bonding. Is it positively charged of negatively charged?

Answer 25

Positive.

Question 26

An atom gains an electron in Ionic bonding. Is it positively charged of negatively charged?

Answer 26

Negative.

Question 27

Why is there an electrostatic force between two oppositely charged ions?

Answer 27

Because opposite Ions attract each other to form an ionic bond.

Question 28

An Atom can only have one covalent bond. True or False?

Answer 28

False, unless the atom only has one electron of it's own. Most atoms can form multiple covalent bonds with different atoms.

Question 29

What does it mean when a molecule has a Double Covalent bond?

Answer 29

They have two shared pairs of electrons.

Question 30

What does it mean when a molecule has a Triple Covalent bond?

Answer 30

They have three shared pairs of electrons.

Question 31

What happens when ice melts and becomes water?

Answer 31

The weak intermolecular forced between the H2O molecules break, but the strong covalent bonds stay together so while the substance itself doesn't break down, it's physical shape does.

Question 32

What kind of structure do macromolecules have?

Answer 32

Giant Covalent.

Question 33

How are giant covalent structures arranged?

Answer 33

In lattices

Question 34

Why is Nitinol used for making braces?

Answer 34

It can be bent to fit the mouth when cool but as the mouth warms up, it reverts back to it's remembered original shape, pulling the teeth with it.

Question 35

What are SMART Materials?

Answer 35

Materials that behave differently to fit different conditions (e.g. temperature).

Question 36

What are Nanoparticles?

Answer 36

Tinier molecules of an atom with different properties to the full sized atom.

Question 37

Why are Nanoparticles used as catalysts?

Answer 37

They have a large surface area ratio meaning that reactions will be quicker as there will be more collisions between particles.

Question 38

What are Polymers?

Answer 38

Long chains of atoms, used to make plastics.

Question 39

Describe a polymer with weak intermolecular forces:

Answer 39

They come in tangled chains (like Spaghetti) and are thermosoftening (soften when heated). They can be melted and reshaped multiple times and have a low density - they are used to make flimsy plastics such as plastic bags or drinks bottles.

Question 40

Describe a polymer with strong intermolecular forces:

Answer 40

They appear in crosslinked chains and do not soften when heated (thermosetting). They are hard, strong and rigid and have a high density. They are used to make heat resistant handles on cookware or laminated worktops.

Question 41

Define Thermosoftening:

Answer 41

Something which melts or softens when heated.

Question 42

Define Thermosetting:

Answer 42

Something which does not melt or soften when heated, but instead retains it's shape.

Question 43

Why are Titanium Dioxide nanoparticles used in Sun Cream?

Answer 43

Titanium dioxide nanoparticles are so small that they do not reflect visible light, so they cannot be seen. They are used in sunblock creams because they block harmful ultraviolet light from the Sun without appearing white on the skin.

Question 44

Why can pure metals be bent and shaped?

Answer 44

Metals are malleable - they can be bent and shaped. This is because they consist of layers of atoms. These layers can slide over one another when the metal is bent, hammered or pressed.

Question 45

What are shape memory alloys?

Answer 45

Shape memory alloys can return to their original shape after being bent or twisted. Nitinol is a shape memory alloy made from nickel and titanium. It is used in dental braces and spectacle frames.

Question 46

What are Fullerenes?

Answer 46

These are cages and tubes with different number of carbon atoms. Buckminsterfullerene is one type of fullerene. Its molecules are spherical and contain 60 carbon atoms. Fullerenes may be used for drug delivery systems in the body, in lubricants and as catalysts.