The Periodic Table Flashcards
How to determine valency electrons
Same as group number
How to determine how many shells of electrons
Period- downwards 1 to 7
Valency
Electrons needed to get full outer shell
Metallic character
Metals lose electrons to form +ve ions, they react with O to form basic oxides, react with non metals to form ionic compounds
Non-metallic character
Gain electrons to form -ve ions, share electrons to form covalent compunds
Properties of alkali metals
Soft, low density, low mp and bp b/c weaker metallic bonds down group, very reactive (increases down group, atoms bigger down)
Lithium with H2O observations
Fizzes and moves slowly, floats on surface
Lithium and water reaction
2Li+ 2H2O->2LiOH+ H2
Sodium obrervations with water
Fizzes faster, Becomes a ball, floats, moves faster
Sodium equation with water
2Na+ 2H2O-> 2NaOH+ H2
Potassium observations with water
Burns lilac flame, becomes a ball, fizzes vigorously, floats
Potassium equation with water
2K+ 2H2O -> 2KOH + H2
Why is a solution alkali
Produces OH
What type of reaction are the alkali metals with the water
Exothermic
Why are alkali metals reducing agents
Give electrons easily, cause substances to be reduced themselves being oxidised
How are halogens
Diatomic
Halogen isnt halide
Chlorine are two atoms joined and chloride is an isotope
Fluorine formula and state
F2, gas and pale yellow
Chlorine formula and state
Cl2, gas and pale green
Bromine formula and state
Br2, liquid and red brown
Iodine formula and state
I2, solid and black purple crystals
Halogens reactivity pattern
Decreases down group as atoms get bigger so more distance less attractive force
Mp and bp of halogens
Larger diatomic molecule means greater intermolecular force and harder to boil or melt (mo and bp decrease down group)
General rule of halogen displacement
Any halogen in molecular form will displace halide ion from below it from a solution of one of its salts (chlorine displaces bromides and iodides, bromine displaces iodides)
Characteristics of transition metals
Form coloured compounds, good catalysts, variable valency and often involved in redox reactions, variable oxidation states, tend to be hard and dense and high mp, relatively unreactive, used to make alloys
Characteristics of noble gases (group 0)
Colourless and monatomic and gaseous, unreactive b/c full outer shell, density more down group as atoms become bigger
Uses of noble gases
Baloons (helium), light signs (neon), headlamps (krypton), arc welding
Chlorine with potassium bromide solution
Cl2+2KBr->2KCl+Br2 (all aq)
Ionic eqt:Cl2 + Br- ->2Cl- +Br2 (all aq)
Colour change: green to red brown
Chlorine with potassium iodide solution
Cl2+2KI-> 2KCl + I2 (all aq)
Ionic eqt: Cl2 +2I- ->2Cl- + I2
Colour change: green to black/purple
Bromine with potassium iodide solution
Br2 +2KI- ->2KBr- +I2
Ionic eqt: Br2+ 2I- ->2Br +I2
Colour change: From red to purple /black
Notes of halogens
Iodine is there if with starch solution turns blue black, iodine used as antiseptic, halogens are soluble in organic solvents and bromine gives brown solution and iodine pink solution
