C2: bonding, structure and properties of matter Flashcards Preview

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Flashcards in C2: bonding, structure and properties of matter Deck (18):
1

Advantages of dot and cross diagrams

Show the bonding in covalent compounds

Shows which atoms the electrons in a covalent bond come from

Show how ionic compounds are formed

2

Disadvantage of dot and cross diagrams

Don’t show the relative sizes of the atoms

How the atoms are arranged in space

Th structure of the compound

The size of the ions

3

Advantage of displayed formula

How atoms are connected in large molecules

4

Disadvantage of displayed formula

Don’t show 3D structure of the molecule
Or
Which atoms the electrons in the covalent bond have come from

5

Advantage to the 3D model

Shows the atoms, covalent bonds and their arrangement

6

Disadvantage of the 3D models

Can quickly get confusing for large molecules where there are lots of atoms to include

They don’t show where the electrons in the bonds have come from

7

Advantage of the ball and stick model

Shows regular patterns of an ionic Crystal

Shows how they are arranged

8

Disadvantages of ball and sick model

Isn’t to scale

In reality there are no gaps between ions

The relative sizes of the ions may not be shown

9

What happens to metals to form ions

They lose electrons form their outer shell to form positive ions

10

What happens to non-metals to form ions

They gain electrons into their outer shell to form negative ions

11

What do dot and cross diagrams show

The arrangement of electrons in an atom or ion

12

What is a regular Lattice structure

Is where ions form a closely packed regular lattice arrangement and there are very strong electrostatic forced of attraction between oppositely chapter ions

13

Similar properties of ionic compounds

High melting and boiling points due to many strong bonds between the ions

When they’re a solid they ions are held in place to they can’t conduct electricity

When they are a substance they are free to move and they can now carry electric current

Dissolve Easily

14

How do hydrogen form a full outer shell

Hydrogen only needs one more electron to complete a full outer shell

They form single covalent bonds either with another hydrogen or with other elements

15

How does oxygen achieve a full outer shell

Oxygen need two more electrons to complete its outer shell

So oxygen atoms share two pairs of electrons with each other making a double covalent bond

16

How does Methane(CH4) complete a full outer shell

Carbon has 4 outer electrons (half a shell)
It can form 4 covalent bonds with hydrogen atoms to full it’s outer shell

17

How does chlorine achieve a full outer shell

Each Chlorine atom needs just one more electron to complete a full outer shell

So 2 chlorine atoms can shed one pair and form a single covalent bond

18

How does nitrogen form a full outer shell

Nitrogen need three more electrons to form a full outer shell

2 nitrogen atoms share three pairs of electrons to fill their outer shells

To create a triple bond