Transition elements Flashcards
What is the definition of a d-block element ?
an element that has its highest energy electron in a d-sub shell
What is the definition of a transition element ?
a d-block element that has an ion with an incomplete sub shell
What two d-block elements are not transition elements ?
- Sc (scandium)
- Zn (zinc)
Why is Sc not a transition element ?
it forms Sc 3+ , which has an empty d-sub shell
Why is Zn not a transition element ?
it forms Zn 2+ , which has a full d-sub shell
What are the three properties of transition elements ?
- variable oxidation states
- used as catalysts
- form coloured compounds in solutions
What is a heterogeneous catalyst ?
a catalyst that is in a different physical state to the reactants
What is a homologous catalyst ?
a catalyst that is in the same physical state as the reactants
What is a complex ion ?
What is a ligand ?
a molecule or ion that can donate a lone pair of electrons to form a coordinate bond with the transition metal ion
What is the coordination number ?
the total number of coordinate bonds formed between the central metal ion and its ligands
