Solve qus no. 22
ans is (c) 9 because isotopes have same atomic no . mass no(a)=14 no of proton=no of electron(A)=7
mass no(B)=16 no of netron(B)=mass no-no proton =16-7=9
mass no(B)=16 no of netron(B)=mass no-no proton =16-7=9