Atoms into ions

Question 1

What is a compound?

Answer 1

A compound contains 2 or more elements which are chemically combined.

Question 2

What is an example of two substances you can mix without a chemical reaction?

Answer 2

Sand and copper sulfate

Question 3

What is the name of the group with a stable electronic configuration?

Answer 3

The noble gases

Question 4

When atoms are unstable they…

Answer 4

…react to take part in changes which give them a stable arrangement of electrons.

Question 5

To maintain a stable electron configuration they may either…

Answer 5

• share electrons, which is called COVALENT BONDING

- transfer electrons, which is called IONIC BONDING

Question 6

In ionic bonding atoms…

Answer 6

lose of gain electrons to form charged particles called ions

Question 7

What electronic structure do the ions have?

Answer 7

The electronic structure of a noble gas.

e.g if sodium (2,8,1) loses one electron, it is left with the stable electronic structure of neon (2,8)

Question 8

What does an atom become when it loses an electron in ionic bonding?

Answer 8

It becomes a positively charged ion because there are now more protons than electrons

Question 9

What is the formula of a sodium ion?

Answer 9

Na+

Question 10

What two substances react with each other in ionic bonding?

Answer 10

A non-metal and a metal

Question 11

When non-metals react with metals, which one gains electrons?

Answer 11

The non-metal gains electrons and the metal tends to lose electrons

Question 12

In ionic bonding when the non-metal atoms gain electrons, what do they become?

Answer 12

Negatively charged ions

Question 13

What is the name of the forces that hold together positively and negatively charged ions?

Answer 13

Electrostatic forces of attraction

Question 14

What do the elements in group 1 react with and why?

Answer 14

They react with group 7 elements as group 1 element only have one electron in their outer shells and need to lose it whereas group 7 elements have 7 electrons in their outer shells and need to gain one in order to gain the stable electronic structure of a noble gas.

Question 15

What do electrostatic forces of attraction result in?

Answer 15

A giant lattice structure

Question 16

What do group one elements form?

Answer 16

1+ ions

Question 17

What do group 2 elements from?

Answer 17

2+ ions

Question 18

What do group 3 elements form?

Answer 18

3+ ions

Question 19

What do group 4 elements from?

Answer 19

Group 4 do not form ions (apart from tin (Sn) and lead (Pb) at the bottom of the group)

Question 20

What do group 5 elements form?

Answer 20

3- ions, when they form ions as opposed to sharing electrons

Question 21

What do group 6 elements form?

Answer 21

2- ions, when they form ions as opposed to sharing electrons

Question 22

What do group 7 elements from?

Answer 22

1- ions, when they form ions as opposed to sharing electrons

Question 23

What do group 0 elements from?

Answer 23

Group 0 never forms ions in compounds

Question 24

What is another example of ionic bonding?

Answer 24

Calcium chloride. Each calcium atom needs to lose 2 electrons but each chlorine atom only needs to gain 1 so EACH calcium atom gives 1 electron to one chlorine atom and another to another chlorine atom. An ion made up of a group of atoms is called a COMPOUND ION.

Question 25

Apart from group 1 and group 7 what groups can form ionic compounds?

Answer 25

Group 2 (forming 2+ ions) and group 6 (forming 2- ions)

Question 26

In what direction do electrostatic forces operate?

Answer 26

All directions

Question 27

Why do ionic compounds have high melting and boiling points?

Answer 27

It takes a lot of energy to break up a giant ionic lattice. There are lots of strong ionic bonds to break. To separate the ions you have to overcome all those electrostatic forces of attraction acting in all directions.

Question 28

Why do ionic compounds conduct electricity when molten or dissolved in water?

Answer 28

Once you have supplied enough energy to separate the ions from the lattice, they become mobile so can start to move around. This is when the ionic solid melt and becomes a liquid. The ions are free to move anywhere in this liquid. They are attracted to oppositely charged electrodes held in the molten compound. Therefore, they can carry their electrical charge through the liquid. In a solution water molecules separate ions from the lattice so it is the same principle.

Question 29

Why can’t a solid ionic compound conduct electricity?

Answer 29

Because its ions are held in fixed positions in the lattice.