early earth, groups, metals Flashcards
What is an ionic lattice?
an ion surrounded by other ions with opposite charges because of attraction. They have strong forces of attraction
Lattices have strong forces of reaction meaning lots of energy is needed to…
they have high melting and bp due to sefc
weaken (melting point) or overcome (boiling point) them.
2 ways to conduct an ionic solid.
Melt using a bunsen burner or dissolve it in water
For a substance to conduct by electricity it needs 2 things:
- To have a charge
- To be able to flow/ move
Metals atoms…
loose electrons to become positively charged cations
non-metal atoms…
gain electrons to become negatively charged anions
What do we know about an element if it ends in ide or ate
ide = it contains 2 elements
ate = it contains 3 or more
Covelent bonds happen between what atoms?
2 non-metal
Allotrope?
Elements with different structural forms.
Why can graphite conduct electricity?
Contains a delocalised 4th electron which is moving around freely.
What is the ionic charge of Mg?
2+
what holds ions together in an ionic bond?
electrostatic forces
describe the bonding of a metal
positive cations surrounded by a sea of delocalised electrons
describe some properties of metals
-strong forces of electrostatic attraction
-generally shiny at room temperature
-contains delocalised electrons allowing it to conduct electricity
-layers of atoms can slide over each other making it malleable
Why does the reactivity in group 1 increase as you go down the group?
because the force of attraction between the positive nucleus and negative outer electron decrease as they become further apart making it easier to remove the outer electron.
give 3 properties of a group 7 element.
diatomic molecules
toxic and corrosive
poor conductors of heat and electricity
How do you test for the presence of chlorine
if damp blue litmus paper is placed in chlorine it first turns red then bleaches white.
What is oxidation and reduction?
oxidation - loss of electrons
reduction - gain of electrons
What happens in all radox reactions?
loss and gains of electrons
What is a rate of reaction?
How long it takes reactants to form into products.
What is activation energy?
Endothermic change
Exothermic change
- The minimum amount of energy needed for a reaction to occur.
- Endothermic reaction is when energy is transferred from surroundings to stores of energy in chemical bons (take in)
- Exothermic reaction when energy is transferred from stores of energy in chemical bonds to the surrounding (release)
List collision theory.
- Concentration- increase in concentration means more collisions
- Temperature - The higher the temp the particles speed up and have more energy therefore more collisions.
- Surface area - The increase of surface area means There’s more surface for the reactions to occur