chemical structures

Question 1

why do ionic structures have such high melting points?

Answer 1

• strong forces of attraction between oppositely charged ions
• requires lots of energy to break

Question 2

why are ionic compounds brittle

Answer 2

• when force is applied ions with the same charge end up next to each other
• like charges repel
• structure falls apart

Question 3

why can‘t ionic compounds conduct when they are solid?

Answer 3

the ions are not free to move around and pass the charge

Question 4

ionic substances compounds can conduct elec when molten/ aqueous because

Answer 4

ions are free to move and can carry the charges

Question 5

metal structure

Answer 5

• positive ions

- sea of delocalised electrons

Question 6

alloy

Answer 6

mixture of two or more metals

Question 7

why do alloys tend to be harder than individual metals?

Answer 7

• they contain ions or elements of different sizes
• layers are distorted
• more difficult for layers to slide over each other

Question 8

malleable

Answer 8

hammered into shape

Question 9

ductile

Answer 9

drawn into a wire

Question 10

why do simple molecular substances have a low melting point?

Answer 10

weak intermolecular forces

require little energy to break