Group 1 Alkaline metal Flashcards
(9 cards)
Alkaline metal + water ->
Metal hydroxide + hydrogen
Lithium
Observation with water
Cut?
Effervescence/fizzes Metal dissapear Floats Move around Heat produced - steam (exothermic reaction)
Indicator turns purple
Hardest to cut out of the alkaline metals
Shiny when cut and becomes dull as it oxidised
Sodium
Melts into a white ball and leaves a white trail
More vigorious reaction than lithium
Effervescence/fizzes Metal dissapear Floats Move around Heat produced - steam (exothermic reaction)
Potassium
Lilac flame produced
Effervescence/fizzes Metal dissapear Floats Move around Heat produced - steam (exothermic reaction)
Indicator turns purple
Easiest to cut fastest to become dull
Safety when reacting group 1 with water
Use small bit of the metal, Safety screen, goggles, gloves, store in oil to prevent water contact, Use large trough with thick glass so it doesnt burst - use large amount of water in large container so energy can be dissapated
Why it gets more reactive moving down group 1
Larger atomic radius
More shells and more shielding
Outer electron has weaker attraction to nucleus (nuclear attraction)
Less energy needed to lose an electron
Shielding outweights the increase nuclear charge (more proton)
Reaction with halogen
White
With oxygen
White smoke,
Why melting point decreases going down the group
Atom get larger, attraction between possitive metal ions and sea of delocaised electrons are weaker