F AND D BLOCK

Question 1

IE TOP TO BOTTOM FOR TRANSITION ELEMENTS

Answer 1

3D TO 4D DECREASE DUE TO SIZE INCR

4D TO 5D INCREASE DUE TO Zeff INCR and same size

Question 2

MELTING AND BOILING POINTS OF TRANSITION ELEMENTS HIGH

Answer 2

DUE TO METALLIC BONDING DUE TO MORE UNPAIRED ELECTRONS

Question 3

HIGHEST OS SHOWN

Answer 3

RUTHENIUM IN 2ND TRANSITION SERIES

OSMIUM IN 3RD TRANSITION SERIES

Question 4

mno4- and cr2O72- show color not due to d-d transition

Answer 4

due to charge transfer

Question 5

d-d transition not shown by fully empty and fully filled orbitals

Answer 5

zn2+.           sc3+
 ag+                 ti4+
au+
cd2+
hg2+

Question 6

most imp ore of chromium

Answer 6

chromite ore or chrome-iron stone

Fe.Cr2O4

Question 7

prep of k2cr2o7

Answer 7

fecr2o4+{na2co3+o2}–> Na2CrO4 yellow
soln
Na2CrO4+H2SO4–? Na2cro7+na2so4+h2o
Na2so4+Kcl–>k2cr2o7+nacl
orange redd crystals

Question 8

why not use na2cr2o7 for titration

Answer 8

hygroscopic

Question 9

green gas when k2cr2o7 heated

Answer 9

cr2o3

Question 10

prep of kmno4

Answer 10

mno2+koh+mno4-o2–> k2mno4

Question 11

chlorides of Pb, Hg,Ag, and Sn don’t give chromyl chloride test

Answer 11

covalent chlorides cannot