Why the white phosphorus more reactive than black phosphorus ???
Answers
White phosphorus has a ring strain. To understand this, let me introduce you a topic of RING STRAIN THEORY.
In cyclo alkane rings, such as cyclopropane, butane (or) pentane etc; there need to have a single angle of 109° 28'. But being considered for other sectors, the angle strain is assumed to be 60°, 120° etc; as that of regular polygon. Due to this it has a deviation from free angle 109° 28'. This is called deviation. If deviation is larger, angle is strained. So, as a consequence internal p.e. increases. So, reactivity increases.
The similar thing happens that white phosphorus possess angle of 60° due to which it suffers strain of 30°. So, to relieve this strain it's reactivity ois more.
Thanking you,
Yours truly,
N.JAYARAMAN
IISc. BENGALURU.
HOD, ORGANIC CHEMISTRY.