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Flashcards in Transition metals Deck (65)
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Whats two key information you need to know on the d-block in the periodic table

1)Occupies the area between groups 2 and 3
2)Contains the transition metals


What is a transition metal

A D-block element that forms one or more stable ions with incompletely filled d-orbitals


Why are scandium and zinc not transition metals

Their ions do not have incompletely filled d-orbital:
All transition metals are d-block elements
.But not all d block elements are transition metals


What can transition metals form

Complexes with ligands such as hydroxide ions and water


What are complexes

Species containing a central metal ion surrounded by ligands bonded to it by dative bonds


Whats a complex ion

Complexes with an overall positive or negative charge


Whats a ligand

A species that can donate at least one pair of electrons to a metal ion, forming a dative bond


Give examples of ligands

water/ ammonia or negative ions such as Cl- and OH-


What is a coordination number

The number of dative bonds in a complex


Whats a monodentate ligand

They can donate one lone pair of electrons to the central metal ion


Whats a bidentate ligand

They can donate two lone pairs of electrons to the central metal ion


What does the shape of a complex ion depend on

The number of ligands around their metal ions


What are octahedral complexes

1)They contain six-fold coordination
2)Have an octahedral shape with bond angle 90 degrees


How is a 3D formulae displayed

1)Solid lines - bonds in the plane of the paper
2)Dashed lines - bonds going behind the paper
3)Wedges - bonds coming out of the paper


When are octahedral complexes usually formed

They are usually formed when the ligands are H2O, NH3, and OH-


What are tetrahedral complexes

1)They have four-fold coordination
2)They have a tetrahedral shape with bond angles of 109.5
3)They usually formed when ligands are relatively large such as Cl-


What are square planar complexes

1)Contain 4 ligands
2)90 degrees
3)an example is [PtCl2(NH3)2]
it has two stereoisomers


What does the systematic name for a complex ion tell you

1)The number and identity of each ligand
2)The identity of the central metal ion and its oxidation number
3)Whether the complex ion is positively charged or negatively charged


How do transition metals form coloured ions in solution

Due to the splitting of the energy levels of their d-orbitals


What happens when an atom or ion absorbs light

An electron is promoted from its normal ground state to a higher excited state


What is an electron transition

A change from one energy level to another


What does the frequency of light absorb depend on

The energy of the transition
The greater the energy of the transition, the higher the frequency of the light absorbed


What happens when white light passes through a solution

Some frequencies of light may be absorbed


What are the colors emerging from the solution called

complementary colors


What happens when ligands bond with a transition metal ion

What does this lead to

electrons in the ligand and electrons in the d-orbital repel each other

As a result
1)the energy levels of the d-orbital increase
2)Two slightly different energy levels form
3)A d electron can be promoted forms lower level tithe high level, f this is partially occupied


What happens when light passes through a solution

Because transition metal ions have incompletely filled d-orbital, Energy in the light promotes an electron from a lower level to a higher level


Why do the d-orbitals in metal ions in octahedral complexes split

to produce two d-orbitals at a higher energy level


Why do the d-orbitals in metal ions in tetrahedral complexes split

To produce three d-orbitals at a higher energy level


What may be a reason why a colour change in transition metal ions may occur

Because of the change in oxidation number, ligand or coordination number


What happens the higher the oxidation number in a given transition metal ion

1)The greater the amount of splitting of the energy levels of the d-orbital by ligands
2)The greater the energy level difference becomes