The ozone layer forms naturally by
the interaction of CFC with oxygen
the interaction of UV radiation with oxygen
the interaction of IR radiation with oxygen
the interaction of oxygen and water vapour
The standard reduction potential E° for half-reaction are
Zn → Zn2+ + 2e- ; E° = + 0.76 V
Fe → Fe2+ + 2e- ; E° = + 0.41 V
The EMF of the cell reaction
Fe2+ + Zn → Zn2+ + Fe is
-0.35 V
+0.35 V
+1.17 V
-1.17 V
Which one of the following is not true at room temperature and pressure?
P4O10 is white solid
SO2 is a colourless gas
SO3 is a colourless gas
NO2 is a brown gas
An element belongs to group 15 and third period of the Periodic Table. Its electronic configuration wil be
1s22s22p3
1s22s22p4
1s22s22p63s23p3
1s22s22p63s23p2
C.
1s22s22p63s23p3
Electronic configuration of Group 15 elements is ns2sp3 and for third period, n = 3. Thus, with electronic configuration 1s22s22p63s23p3, the element is phosphorus.
Platinum, palladium and iridium are called noble metals because
Alfred Nobel discovered them
they are shining lustrous and pleasing to look at
they are found in native state
they are inert towards many common reagents
Which of the following represents the composition of camallite mineral?
K2O.Al2O3.6SiO2
KNO3
K2SO4.MgSO4.MgCl2.6H2O
KCl.MgCl2.6H2O
Anhydrous ferric chloride is prepared by
dissoving Fe(OH)3 in concentrated HCl
dissolving Fe(OH)3 in dilute HCl
passing dry HCl over heated iron scrap
passing dry Cl2 gas over heated iron scrap