Question

calculate number of neutrons present in 12 X10^25 atoms of oxygen

Answer 1

in 1 atom of oxygen
mass= no. of proton+no. of neutron
so
16=8+no. of neutron
so no of neutron in 1 atom is 8
so
in 12×10^25 has
8×12×10^25=96×10^25 neutron