c2.2 try 2

Question 1

metals:
- appearance
- melting point + boiling point
- state at room temp
- malleable or brittle
- ductile or non ductile
- electrical + thermal conductivity

Answer 1

-shiny
- usually high
- solid
- malleable
- ductile
- good conductors of both

Question 2

non- metals:
- appearance
- melting point + boiling point
- state at room temp
- malleable or brittle
- ductile or non ductile
- electrical + thermal conductivity

Answer 2

• dull
• usually low
• half solid, half gas
• brittle
• non-ductile
• poor conductivity (insulators)

Question 3

where are metals and non-metals positioned on the periodic table?

Answer 3

non metals = right
metals = left

Question 4

how do metals and non-metals differ in terms of how they form ions?

Answer 4

• metals lose electrons when forming ions (positive ions)
• non-metals gain electrons when forming ions (negative ions)

Question 5

what kind of solution is produced when a metal oxide dissolves in water? (acidic or alkaline)

Answer 5

alkaline solution

Question 6

what kind of solution is produced when a non-metal oxide dissolves in water? (acidic or alkaline)

Answer 6

acidic solution

Question 7

what is special about the elements on the boundary of non metals and metals on the periodic table?

Answer 7

some elements have properties of both metals and non-metals

Question 8

how is an ion formed?

Answer 8

when an atom or group of atoms loses or gains electrons

Question 9

draw a dot and cross diagram of a chloride ion (atomic number of 17)

Answer 9

2 in first shell, 8 in second shell, 8 in third shell (8th electron must be different to other electrons), as it gains one electron

Question 10

what kind of bond is formed when sodium and chlorine react?

Answer 10

an ionic compound (as they are a metal and non-metal respectively)

Question 11

what happens when a metal and non-metal reacts (in terms of electrons), and why does that happen? (2)

Answer 11

an electron/electrons are transferred from the metal to the non-metal (1) so that they both have stable electronic structures (1)

Question 12

what is the structure of an ionic compound? (in solid state) (2)

Answer 12

• they are regularly (1) arranged with opposite charged ions alternating (1)
  ie. + - + - + - + - +

Question 13

what is the name of the arrangement of an ionic compound?

Answer 13

giant ionic lattice

Question 14

explain how strong ionic bonds are. (3)

Answer 14

VERY STRONG (1)
- forces of electrostatic attraction between oppositely charged ions (1) caused by transfer of electrons (from metal to non-metal) (1)

Question 15

what is a covalent bond (in terms of electrons)? (1)

Answer 15

a shared pair of electrons

Question 16

why do covalent bonds form?

Answer 16

so that both the non-metal atoms can complete their outer shells

Question 17

how is a covalent bond shown on a dot and cross diagram?

Answer 17

like a venn diagram, with however many shared electrons in the overlapping section (o x) is one pair of shared electrons

Question 18

give 4 examples of simple molecules?

Answer 18

hydrogen, oxygen, water, carbon dioxide

Question 19

where is the force of attraction in simple molecules, and what kind of bonds are they?

AND RELATIVE STRENGTH

Answer 19

• force of attraction between nucleus of bonded atom + shared electron -> COVALENT bond - strong
• forces between molecules -> INTERMOLECULAR - weak

Question 20

limitations of ball-and-stick models? (3)

Answer 20

• size of atom is exaggerated
• length of bond is exaggerated
• suggests that electrons (that make up bonds) do not move

Question 21

main limitation of a displayed formula model? (1)

Answer 21

• does not show 3D shape of the molecule

(looks like this)
O
/ \
H H

Question 22

how are the reactions of elements related to the arrangement of electrons in their atoms?

Answer 22

they react in a way to have the most stable arrangement (ie. a full outer shell)

Question 23

state 3 properties of Mendeleev’s periodic table

Answer 23

• mainly ordered his table in order of increasing atomic mass (some places he changed order based on properties)
• rows and columns for chemical properties
• left gaps for elements he thought had not been discovered yet