Number of neutrons present in 3.2 grams of methane is equal to (assume methane contains C-12  and  H-1  isotopes)

Number of fundamental particles in carbon = 6p + 6e + 6nNumber of fundamental particles in hydrogen = 1p + 1eNumber of fundamental particles in methaneCH4 = 10p + 10e + 6nGMW  of  CH416g  contains  6NA  neutrons 3.2g  contains 'X' neutrons X=3.216×6NA=1.2NA=7.2×1023