Chapter 3 - Chemical Bonding

Question 1

what is an element?

Answer 1

a substance that cannot be further divided into simpler substances by chemical methods; contain the same number of protons

Question 2

what are metals?

Answer 2

a class of chemical elements (and alloys) that all have a characteristic shiny appearance and are good conductors of electricity

Question 3

what are non-metals?

Answer 3

a class of chemical elements that are typically poor conductors of electricity and heat

Question 4

what is a compound?

Answer 4

a substance formed by the chemical combination of two or more elements in a fixed proportion

Question 5

what is a chemical formula?

Answer 5

a shorthand method of representing chemical elements and compounds using the symbols of the elements

Question 6

what is meant by chemical bonding?

Answer 6

the strong forces that hold atoms (or ions) together in the various structures that chemical substances can form - metallic bonding, ionic bonding and covalent bonding

Question 7

what are diatomic molecules?

Answer 7

molecules containing two atoms

Question 8

what is covalent bonding?

Answer 8

chemical bonding formed by the sharing of one or more pairs of electrons between two atoms

Question 9

what is a dot-cross-diagram?

Answer 9

a diagram drawn to represent the bonding in molecules or the electrons in an ion; usually only the outer electrons are shown

Question 10

what is ionic bodning?

Answer 10

a strong electrostatic force of attraction between oppositely charged ions

Question 11

what are ions?

Answer 11

charged particles made from atoms or groups of atoms (compound ions) by the loss or gain of electrons

Question 12

what are electrostatic forces?

Answer 12

strong forces of attraction between particles with opposite charges such as forces involved in ionic bonding

Question 13

what are cations?

Answer 13

a positive ion that would be attracted to the cathode in electrolysis - lose electrons (metals)

Question 14

what are anions?

Answer 14

a negative ion that would be attracted to the anode in electrolysis - gain electrons (non-metals)

Question 15

what is meant by giant ionic lattice (structure)?

Answer 15

a lattice held together by the electrostatic forces of attraction between positive and negative ions

Question 16

what are giant structures?

Answer 16

lattices where the structure repeats itself in all directions; the forces involved are the same in all directions holding the whole structure together

Question 17

what is meant by giant covalent structures?

Answer 17

a substance where large numbers of atoms are held together by covalent bonds forming a strong lattice structure

Question 18

what is meant by giant metallic lattice?

Answer 18

a regular arrangement of positive metal ions held together by the mobile ‘sea’ of electrons moving between the ions

Question 19

what is meant by the term ‘sea’ of delocalised electrons?

Answer 19

term used for the free, mobile electrons between the positive ions in metallic lattice

Question 20

what is meant by metallic boding?

Answer 20

an electrostatic force of attraction between the mobile ‘sea’ of electrons and the regular array of positive metal ions within a solid metal

Question 21

what is meant is something is malleable?

Answer 21

can be bent and beaten into sheets

Question 22

what is meant is something is ductile?

Answer 22

can be drawn out and stretched into wires