physical properties Flashcards
d block elements have one or more typical metallic structure except for 4 metals. name them
zn, cd , hg, mn
why do d block elements have high mp and bp?
incolvement of greater no of e from (n-1)d in addition to the ns electrons in the interatomic metallic bonding.
metals of 2nd and third series have ___ enthalpies of atomisation than 1st series thus we see more _ bonding in heavier elements
greater
metal-metal
what is the consequence of lanthnoid contraction?
similar radii of 2nd and 3rd radii
what is the cause of lanthanoid contraction
imperfect shielding of an electron by another present in the same orbital
the shielding of 4f orbital is____ than that of one d orbital
less
enthalpy of atomisation is highest and least for ?
vanadium - highest
zinc- least
why is there an irregular trend in first ionisation enthalpy in the metals of 3d series
removal of one electron alters the relative energies of 4s and 3d orbitals
why is there an increase in second ionisation enthalpy?
one d e- does not shield another e- as both differ in direction
when does the trend of inc in second ionisation and third enthalpy decrease ?
second- by the formation of Mn2+
third- Fe2+
which energy is responsible for the stabilisation of energy state
exchange energy
exchange energy is proportional to ?
total number of possible pairs of parallel spin in the degenerate orbitals
there is no loss of exchange energy at __ configuration
d6
which one has more ionisation enthalpy?
Mn+ & Cr+
Mn2+ & Fe2+
cr
mn
what is the lowest common ox st of d block elements
+2
which d block element shows only +2 ox st
sc
which d block element shows only +3 ox st
sc
in d block the highest oxidation states are acquired by what molecules
Tix4, CrF6, VF5
beyond mn no halide has trihalides except?
fex3, CoF3
fluorine stabalises ox st of compounds like CoF3 bcs of __ and VF5 CrF6 bcs of __
cof3- higher lattice energy
vf5 and crf6- higher covalent compounds
why is cu2+ more stable than cu+
bcs higher hydration enthalpy of cu2+ which compensates for second ionisation enthalpy of cu
what is highest mn fluoride and mn oxide
mnf4 and mn2 o7
in mn2o7 how are mn surrounded by o molecules
tetrahedrally
which d block element has positive M2+/M value?
cu
the E- value of what metals are more negative than expected
Mn ni zn
mn3+ n co3+ are strongest ____ agent
oxidising
which ions are strongest reducing agent
ti2+ v2+ cr2+
ferromagnetism is extreme form of _
paramagnetism
substances that are attracted by applied field are ?
diamagnetic
