Question

What will be the equivalent weight of h3po2 when it devides into ph3 and h3po3?

Answer 1

the balanced reaction for this disproportionation is:

3H3PO2--->2H3PO3 + PH3

Now the conversion of H3PO2 to PH3 involves the addition of 4 electrons. For balance there must be 4 electrons in the the other conversion as well. Now the n factor here is given by

no. of electrons involved/total no. of molecules in the reaction

=4/3.

Hence equivalent weight= M/n-factor

=3M/4.