TRANSITION ELEMENTS Flashcards
WHAT IS THE ORDER OF SUB SHELLS IN INCREASING ENERGY
1s 2s 2p 3s 3p 4s 3d 4p 4d
What is a transition element
a d block element that can form at least one stable ion with a partially filled d subshell
Which period 4 metals are not transition elements
scandium and zinc as they don’t form a stable ion
Which 2 transition metals form a 4s1 shell
Copper and Chromium
as an electron in the 4s sub shell will jump to form a half filled or fully filled 3d shell that is more stable
Why is scandium not a transition element
as its only stable ion (Sc3+) has an empty d subshell, which is not partially filled
Why is Zinc not a transition element
As it has one stable ion (Zn2+) which has a fully filled d subshell, which is not partially filled
3 properties of transition metals
variable oxidation states - as electrons sit in 4s and 3d sub shells
form coloured ions in solution
good catalysts
Vanadium ions and their colours
V2+ - violet
V3+ - green
VO2+ - blue
VO3+ - yellow
Chromium ions and their colours
Cr3+ - green/violet
Cr2O72- - orange
Manganese ions and their colours
Mn2+ - pale pink
MnO42- - green
MnO4- - purple
Iron ions and their colours
Fe2+ - pale green
Fe3+ - yellow
Cobalt ions and their colours
Co2+ - pink
Nickel ions and their colours
Ni2+ - green
Copper ions and their colours
Cu2+ - blue
Titanium ions and their colours
Ti2+ - violet
Ti3+ - purple
How are transition metals good catalysts
they can receive and lose electrons in the d - orbital to speed up reactions
they allow substances to aDsorb to their surfaces which lowers the activation energy of a reaction
Risks of transition elements as catalysts
Long term exposure of copper can cause liver damage
long term exposure to manganese can cause physical tremors
Cu2+ with OH- or NH3
and addition of OH- to precipitate
Addition of NH3 to precipitate
pale blue precipitate
Cu(OH)2(H2O)4
insoluble in excess NaOH so no change
Dark blue solution( part ligand substitution)
[Cu(NH3)4(H2O)2]2+
Fe2+ with OH- or NH3
and addition of OH- to precipitate
Addition of NH3 to precipitate
Dirty green precipitate
Fe(OH)2(H2O)4
insoluble in excess NaOH so no change
insoluble in excess NH3 so no change
Fe3+ with OH- or NH3
and addition of OH- to precipitate
Addition of NH3 to precipitate
Orange - brown precipitate
Fe(OH)3(H2O)3
insoluble in excess NaOH so no change
insoluble in excess NH3 so no change
Mn2+ with OH- or NH3
and addition of OH- to precipitate
Addition of NH3 to precipitate
Pink precipitate
Mn(OH)2(H2O)4
insoluble in excess NaOH so no change
insoluble in excess NH3 so no change
Cr3+ with OH- or NH3
and addition of OH- to precipitate
Addition of NH3 to precipitate
Green-grey precipitate
Cr(OH)3(H2O)3
Dark green solution
Cr(OH)63-
Purple solution(full ligand substitution)
[Cr(NH3)6]3+