# A Hard and resistant alloy generally used in tip of nib of pen is : Option 1) $Os, Ir$ Option 2) $Pt, Cr$ Option 3) $V , Fe$ Option 4) $Fe, Cr$

P Plabita

As we learnt in

Magnetic properties -

when a magnetic field is applied to a substance of metals, they show generally two types of magnetic behaviour

1.  Diamagnetism

2.  Paramagnetism

-

KMmO4, in this compund, the O.S. of Mn is +7 and it's d-orbitals are vacant. With no unpaired electrons, the compound is diamagnetic.

Option 1)

$Os, Ir$

Option 2)

$Pt, Cr$

Option 3)

$V , Fe$

$Fe, Cr$