Transition Elements Flashcards
What owes to the colour of the compounds of transition elements?
Electrons of transition metal ions in partially filled d-orbital are able to absorb light and migrate to higher energy orbitals.
Which transition metal ions are colourless and why?
Ti+4 and Sc+3: they have empty d-orbital.
Zn+2: it has a fully filled d-orbital.
Describe the magnetism of compounds of transition elements.
Transition element compounds with unpaired electrons are paramagnetic (attracted by magnetic field) while those with all paired electrons are diamagnetic (no attraction; is repelled)
Describe the complex compound formation of transition elements.
Transition elements are good at forming complexes due to their small but high charge density ions, and vacant low energy orbitals which can be filled by lone pairs donated by ligands.
How are transition elements different from other elements when it comes to atomic radius?
Atomic radius for transition elements does not decrease steadily across the period. This is because electrons are added to the d orbital as atomic number increases, shielding the outer electrons from the positively charged nucleus. This results in a relatively constant size.
Why do transition elements have varying oxidative stes?
The valence electrons of transition elements exist in two different orbitals. Because the energy difference between the two orbitals is small, both can be used in bond formation.
What is the oxidation number of CN?
-1
What is the oxidation number of H2O?
0
What is the oxidation number of “en” (ethylenediamine)?
0
What is the oxidation number of NO2 (Nitro)?
-1
What is the oxidation number of C2O4 (oxylate)?
-2
What are the examples of low spin lignards?
CO, CN, NO2.
What are examples of high spin lignards?
H2O, NH3, C2O4, X-1
Which spin lignards cause anti-Hund rule?
Low spin lignards.
