C2 Periodic Table Flashcards
(73 cards)
Why ordering of elements changed overtime
New elements were being found and scientists needed to rearrange them by relative atomic mass
How the electronic structure of metals and non-metals are different
Atoms of metal give away electrons to form positive ions
Atoms of non-metal gain electrons to form negative ions
How the electronic structure of metals and non-metals affects their reactivity
If an atom has more electrons than protons its reactivity increases
How electronic structure is linked to the periodic table
The number of electrons in outermost shell depends on the group number the element is in
How to use the periodic table to predict reactivity of elements
For metals reactiviy increases down a group
Reactivity decreases moving left to right along a period
Why are noble gases unreactive
The atoms of noble gases already have complete outer shells so they have no tendency to lose, gain or share electrons
How to predict which ions are stable
How easily an element can achieve a full outer electron shell
Properties of group 1 metals
Soft
Reactive
Low melting points
Good conductors of heat and electricity
Low density
Why elements in group 1 react similarly
They all have 1 electron in their outer shell
Why do the first 3 elements of group 1 float on water
Less dense than water
Equation for group 1 metals react with water
2X(s) + 2H2O(s) —> 2XOH(aq) + H2(g)
How you can show that hydrogen and metal hydroxides are made when Group 1 metals react with water
Hydroxides dissolve in water to form alkaline solutions
They are purple showing they are strongly alkaline
How Group 1 metals are stored and the safety precautions used when dealing with them
Stored in mineral oil or kerosene
Do not expse to air or water
How to recognise a halogen displacement reaction
Reaction mixture turns darker and iodine solution forms
Why elements in group 7 react similarly
Same number of electrons in outer shell
Main properties of halogens
Form negative anions
More dense as go down group
Poor conductors of heat and electricity
Brittle
How to complete a halogen displacement reaction
2 drops potassium chloride to each 3 dimples in column 1 of tile
2 drops potassium bromide solution to each of 3 dimples in column 2
2 drops potassium iodide solution to each of 3 dimples in column 3
What happens in halogen displacement reaction
The more reactive halogen atoms oxidise the less reactive halide ions
causing halide ions to lose electrons and form halogen atoms
Trend in reactivity group 1 metals
Increases as you go down the group
Reactivity of group 7
Decreases as go down the group
Why group 1 reactivity increases as go down the group
As go down the group
Atoms get larger
Outer electron gets further from nucleus
Attraction between nucleus and outer electron gets weaker so electron is easily more lost
Why group 7 reactivity decreases as go down the group
As you go down the group
Atomic mass of halogens increases
Increases in electron shells
Atoms get larger as go down the group therefore attraction of outer electron to nucleus decreases as you go down group 7
Trend in group 1 boiling point
Decreases
Why group 1 boiling point decreases as go down the group
As go down the group there are more protons, electrons, neutrons and energy levels to the atoms
Atoms get larger
As atom increase in size attractive forces decrease since internuclear distance increases
This leads to lower boiling and melting temperatures
