Bonding and Structure 1

Question 1

What are ions?

Answer 1

Charged particles that is formed when an

atom loses or gains electrons

Question 2

What is the charge of the ion

when electrons are gained?

Answer 2

Negative

Question 3

What are molecular ions?

Answer 3

Covalently bonded atoms that lose or

gain electrons

Question 4

Which electrons are lost when
an atom becomes a positive
ion?

Answer 4

Electrons in the highest energy levels

Question 5

Do metals usually gain or lose

electrons?

Answer 5

Lose electrons

Question 6

Which are the 4 elements that
don’t tend to form ions and
why?

Answer 6

The elements are beryllium, boron, carbon
and silicon
Requires a lot of energy to transfer outer shell
electrons

Question 7

What are the 3 main types of

chemical bonds?

Answer 7

● Ionic
● Covalent
● Metallic

Question 8

Define ionic bonding

Answer 8

The electrostatic attraction between

positive and negative ions

Question 9

Give an example of an ionically bonded substance

Answer 9

NaCl (Sodium Chloride - salt)

Question 10

What determines the strength of an ionic bond?

Answer 10

• Ionic radius and ionic charge
• Ionic bonding is stronger and the melting points
  higher when the ions are smaller and/ or have
  higher charges.

Question 11

Explain the trend in ionic

radius down a group

Answer 11

Ionic radii increase going down the group.

This is because down the group the ions have more
shells of electrons and thus the outermost electron experience less pull from the positive nucleus.

Question 12

Explain the trend in ionic radius for this set of isoelectronic ions,
e.g. N3- to Al3+

x
| x
| x
| x
| x
| x
|________________________________
N3- O2- F- (Ne) Na+ Mg2+ Al3+

Answer 12

There are increasing numbers of protons from N to F
and then Na to Al but the same number of electrons.
Therefore nuclear attraction between the outermost
electrons and nucleus increases and ions get
smaller

Question 13

What are the physical
properties of ionic
compounds?

Answer 13

• high melting points
• non conductor of electricity when solid
• conductor of electricity when in solution or molten
• brittle /

Question 14

In a solution of CuCrO4 with connected electrodes which electrode will the 2 ions migrate to?

Answer 14

Cu 2+ &raquo_space; migrates to negative electrode

CrO4 2- &raquo_space; migrates to positive electrode

Question 15

Define covalent bonding

Answer 15

Electrostatic attraction between a shared

pair of electrons and the nuclei

Question 16

Define metallic bonding

Answer 16

Electrostatic attraction between the
positive metal ions and the sea of
delocalised electrons

Question 17

Electrons in which shell are
represented in a dot and cross
diagram?

Answer 17

The outer shell