Question

assertion and reason ... it , question no. 4

Answer 1

assertion is right and reason is correct explanation

Answer 2

H3PO4 is a acid....
with basicity=3=n factor
{ basicity= no. of replaceable H+ions..}
but here... as we can see in the give reaction that H3PO4 ---> Na2HPO4.......
=> here only 2 H+ion are lost
=> n= 2 in this case....

so.... equivalent weight of H3PO4 IN THIS CASE will be ( molecular mass of H3PO4)/n factor i.e. no. of H+ replaced...i.e. basicity

=>E= M/n-factor
{where M= molecular mass of H3PO4...}
=> E=M/2. {in the given reaction}

=> both the assertion and reason are correct....
=> mark option (1)....


hope it helps you...
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