General trends of TM Flashcards
up until Mn, what is the highest oxidation state the same as?
Group number
What happens once you pass Mn?
High oxidation states equal to the group number aren’t observed
What are the thermal and electrical conductivities like in d-block metal?
They are high
What are other physical properties of transition metals?
Most are hard, ductile and malleable
What does ductile mean?
Ability to be stretched or pressed into a shape without heating
What does malleable mean?
Ability to be shaped easily without breaking
Which metal structures are usually possessed by transition metals?
Hexagonal closely packed (HCP)
Cubic closely packed (CCP)
Body centred cubic (BCC)
What are the metallic radii (rmet) like compared to s-block metals?
Smaller
Which metals don’t follow the same structure trends?
Mn
Zn
Cd
Hg
What is the trend like for rmet from Sc to Ni?
Decreases slightly from Sc (144pm) to Ni (115pm)
Why is there a slight decrease in rmet across a row?
The effective nuclear charge increases because of poor shielding of the d-electrons
What are the trends in rmet like for second and third rows compared to the first row?
they are greater
Why does a valence electron experience an effective nuclear charge?
“inner” core electrons can screen it from the true nuclear charge
What does effective nuclear charge depend on?
Values of n and l of the electrons
Which orbital electrons are good and bad at shielding?
S orbital electrons are good at shielding
d and f orbitals are bad at shielding
What is the lanthanide contraction?
Steady increase in size along the series of elements La to Lu
What is the overall lanthanide contraction increase?
0.25 Å
When moving from the second row to the third row, what must we do?
we must add in the lanthanide metals after Lanthanum
What is the lanthanide contraction due to? What does it lead too?
Due to imperfect shielding of one electron by another but this time by f-electrons, leading to a steady increase in effective nuclear charge
What does the lanthanide contraction offset?
The expected increase in size down a group
