The phenomenon in which polar crystals on heating produce electricity is called:-
Which arrangement of electrons leads to anti-ferromagnetism?
(c) Both (a) and (b)
(d) None of these
A spinel is an important class of oxides consisting of two types of metal ions with the oxide ions arranged in ccp layers. The normal spinel has 1/8th of the tetrahedral void occupied by one type of metal and one half of the octahedral voids occupied by another type of metal ions. Such a spinel is formed by Zn2+, Al3+ and O2- with Zn2+ in tetrahedral void. Give the simplest formula of the spinel.
(D) None of these
What type of substances would make better Permanent Magnets:
Ferromagnetic or Ferrimagnetic?