T2 YR10 - Periodic table Flashcards
What law did John Dalton come up with?
Law of atomic weight
Who came up with the “law of octaves”?
John Newlands
Who left gaps for undiscovered elements in the periodic table?
Dimitri Mendeleev
Name one similarity and one difference between Newlands and Mendeleevs table?
Both were in the same order of atomic weight but Mendeleev realises they didn’t match the order of reactivity
What tells us the amount of electrons on an outer shell?
The group that the element is in
What is a non-metals state at room temperature?
Gas
What is a metals strength?
High
What would you see within a reaction of lithium and water?
Turned into a gas, moved on the surface and effervescence
Describe pattern in reactivity in group 1 as you go down the group?
Become more reactive and violent than the previous reaction
How come the further down the group the more reactive the metal?
It is harder to lose electrons due to force between protons within nucleus and outer shell electrons means shielding prevents electrons being lost
What are the typical physical properties of group 7
2 of the elements are a gas at room temp, they form diatomic molecules and form coloured vapour
How does boiling and melting point change as you go down the group?
Atomic number increases and so does melting point
What is the trend in reactivity as you go down group 7?
Elements get less reactive as you go down
What is group 7 called?
The halogens
What is shielding?
The force between the nucleus and outer shell making it harder to lose electrons therefore the gain electrons instead
What is the order of displacing?
Bromine, chlorine, iodine
How does melting point change within alkali metals?
It decreases further down the group
Were isotopes discovered after Mendeleev?
Yes
In what order is the modern periodic table arranged?
Atomic number
How do boiling points halogens change as you go down the group?
They increase
