Which of the following is a polar molecule?
BF3
SF4
SiF4
XeF4
B.
SF4
Symmetrical molecules are generally non-polar although they have polar bonds. This is because bond dipole of one bond is cancelled by that of the other. BF3, SiF4 and XeF4 being symmetrical as non-polar. SF4 is unsymmetrical because of the presence of a lone pair of electrons. Due to which it is a polar molecule.
Of the following acids the one which has the capability to form complex compound and also possesses oxidising and reducing properties is
HNO3
HNO2
HCOOH
HCN
Atoms in a P4 molecule of white phosphorus are arranged regularly in the following way
at the corners of a cube
at the corners of an octahedron
at the corners of a tetrahedron
at the centre and corners of a tetrahedron
Which one of the following pairs is obtained on heating ammonium dichromate?
N2 and H2O
N2O and H2O
NO2 and H2O
NO and NO2
When KI is added to acidified solution of sodium nitrite, then
NO gas is liberated and I2 is set free
N2 gas is liberated and HI is produced
N2O gas is liberated and I2 is set free
N2 gas is liberated and HOI is produced
Give the structure of pyrphyuric acid. How would you prepare it? What would you observe when colourless HI is added to pyrphuric acid ?
Which of the following electronic configuration represents noble gas ?
ns2np6
ns2np5
ns2np4
ns2np3