Periodic Table - S BLOCK Flashcards
S block overview
S block elements lose e-, they are readily oxidised. As they give e- to other species they are called oxidising agents
Group 2 and Water - general
Effervesence, Basic solution produced
Group 2 and Water - Trend
Reactivity increased going down the group due to; Reduced effective nuclear charge, greater shielding, larger atomic radius.
Group 2 and Water Equation
2Xx + 2H20 –> 2XxOH + H2
Group 2 and Acids - General
Effervescence, neutralises acid. Heat and hydrogen produced
Group 2 and Acids - Trend
Reactivity increased going down the group due to; Reduced effective nuclear charge, greater shielding, larger atomic radius.
Group 2 and Acids - Equation
Xx + HYy –> XxYy (Salt) + H2)
S block Oxides and Hydroxides - Overview
Generally metal oxides are basic, non metal oxides - acidic. Reactions with water produces basic/acidic solutions
S block metal oxides (Ba and group 1 only) and water
Produces alkali, Oxides dissolve. Oxygen piece of water molecule heavily electronegative. Thus hydrogen breaks off as it is electron deficient and bonds to roaming O2- ion. Producing 2OH-. Metal ion bonds to OH- Ion.
Why don’t another group 2 metals react in this way?
They are not very soluable - saturated, highly charge dense, smaller atomic radius.
** Soluablity Patterns - General **
Group 1 - All soluable
Group 2 - Patterns to remember
Nitrates - All soluble
Carbonates - None Soluable
Group 2 Sulfates
More Soluble at higher periods. Mg Soluable. Ca, Sr and Br insoluable
Group 2 hydroxides
More soluble at lower periods. Ba, Sr Soluble. Mg, Ca not.
Thermal Stabilty - Hydroxides
All group 2 hydroxides decompose on heating to produce metal oxides and stram
Thermal Stabilty - Carbonates
All group 2 Carbonates decompose on heating to produce metal oxides and steam.
