C3- structure and bonding

Question 1

What is an ion?

Answer 1

A particle that is electrically charged.

Question 2

What is a covalent bond?

Answer 2

The attraction between 2 atoms that share 1 or more pairs of electrons.

Question 3

What do you call it when something goes from gas to liquid?

Answer 3

Condensing

Question 4

What do you call it when something goes from liquid to gas?

Answer 4

Evaporation

Question 5

The amount of energy required to change state from solid to liquid, and from liquid to gas depends on what?

Answer 5

The strength of forces between the particles of a substance.

Question 6

The stronger the the force of attraction…?

Answer 6

The more energy required to change state

Question 7

What do you call it when a substance goes from solid to gas?

Answer 7

Sublimination

Question 8

What do you call it when a substance goes from gas to solid?

Answer 8

Deposition

Question 9

Is freezing or melting exo or endothermic

Answer 9

Freezing is exothermic
Melting is endothermic

Question 10

What is the difference between boiling and evaporation?

Answer 10

Evaporation occurs at any temperature and boiling is evaporation at its furthest state where the particles have enough energy to change state.

Question 11

In a heating/cooling curve what goes on the x and y axises?

Answer 11

On the X is time and on the Y is temperature.

Question 12

What is a cation and anion?

Answer 12

A cation is a positive ion and a anion is negative

Question 13

What is meant by the term ‘noble gas configuration’?

Answer 13

When the outer shell is full

Question 14

What is a redox reaction?

Answer 14

When oxidation and reduction happen at the same time ( when one atom transfers an electron to another atom).

Question 15

What is an ionic equation?

Answer 15

When you do a symbol equation but only showing the particles that take place in the reaction.

Question 16

What is a half equation?

Answer 16

When you write an equation for one element in a reaction showing the loss or gain of electrons.

E.g. (Ca)—> (Ca^2+) + (2e-)

Question 17

What does isoelectronic mean?

Answer 17

It means two substances with the same electron configuration.

Question 18

What ions do group 1,2,3,5,6 and 7 form?

Answer 18

Group 1 form 1+ ions
Group 2 form 2+ ions
Group 3 form 3+ ions
Group 5 from 3- ions
Group 6 form 2- ions
Group 7 form 1- ions

Question 19

What is ionic bonding?

Answer 19

Ionic bonding is the strong electrostatic attraction between many oppositely charged ions.

Question 20

Why do ionic compounds have such high boiling and melting points?

Answer 20

As there are so many bonds that need to be broken to separate the ions that it requires a lot of energy.

Question 21

What type of bonding is water?

Answer 21

Covelant

Question 22

What type of bonding is a fluorine molecule?

Answer 22

Covelant

Question 23

What are the physical properties of giant covelant structures?

Answer 23

• have very high melting and boiling points
• are not soluble In water
  -very hard and do not conduct electricity.

Question 24

What is an allotrope?

Answer 24

Different structural forms of the same elements. They can have different physical and structural properties

Question 25

What are some examples of allotropes of carbon?

Answer 25

Diamond, graphite, buckminsterfullerine, graphene

Question 26

How should you structure a question on the why a material is suitable for a curtain job.

Answer 26

1) state structure
2) state bonding
3) properties
4) link back to question

Question 27

Describe the structure of metalic bonding?

Answer 27

The metal cations are positioned in a regular lattice, with the delocalised vailence electrons randomly placed around them which makes the bonding very strong.

Question 28

Why does the metalic bonding diagram show the properties of metal?

Answer 28

-delocalised electrons can freely move throughout the structure (increased conductivity)
- when hit the ion layers can slide over each other, as do the delocalised vailence electrons move too preventing the ions from propelling each other.

Question 29

What is an alloy?

Answer 29

An alloy is a mixture of chemical elements where the primary component is a metal.

Question 30

Why do we use alloys instead of pure metals?

Answer 30

-in pure metals, it is easy for the layers to slide over each other, explaining why pure metals are soft.
-in an alloy, the atoms are different sizes, distorting the layers making it harder for the layers to slide over each other. The alloy is stronger and harder than pure metal

Question 31

How are ionic compounds held together?

Answer 31

• held together by a giant lattice.
• regular structure that extends in all directions in a substance
• electrostatic attraction between positive and negative ions holds the structure together

Question 32

Properties of ionic substances?

Answer 32

• high melting and boiling points ( strong electrostatic forces of attraction)
• do not conduct electricity when solid ( ions in fixed positions)
• conduct when dissolved in water or liquid as ions are then free to move.

Question 33

What are the pros and cons of dot and cross diagrams?

Answer 33

Pros:
- easy to visualise transfer of electrons.
- show clearly which electrons came from where
- show changes of ions
Cons:
- don’t show structure of the compound
- don’t correctly represent size of ions
- fails to represent delocalised electrons