Number of neutrons present in 6.4 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 methane ( CH4 ) = 10p + 10e + 6nGMW  of  CH416g  contains  6NA  neutrons                        6.4g  contains 'X' neutrons X=6.416×6NA=2.4NA=1.44×1024 ;