Question

In  a  triad  of  ‘A’,  ‘B’,  ‘C’  elements,  if  the  atomic  mass  of  ‘B’  and
‘C’  are  150  and  200  respectively,  the  atomic  mass  of  ‘A’  is,
a.  100. b.  125.
c.  250. d.  350.

DSERT Class 10 Science Ch 3 Periodic Classification of Elements

Answer 1

In a given triad we have A/2+C/2= B On transposing we have A/2= B-C/2 In putting the values we get A/2= 150-200/2 So. A/2 = 150-100 Therefore A/2= 50 thus we have A= 100 Atomic mass of A is 100