A sample of sodium has a mass 46gm what is the mass of the same number of calcium atoms as sodium atoms present in given sample

atomic mass of sodium= 23 g/mol
moles of sodium atoms in 46 gm= 46/23 = 2 moles
as mentioned in question, no of Na atoms = no of atoms of Ca atoms.
therefore no of atoms of ca atoms= 2 moles
therefore mass of 2 moles of Ca atoms = 2 x atomic wt of Ca = 2 mol x 40 g/mol = 80 g
Therefore answer is 80g.

Mass of one atom is 3.32×10×_23. Now weight of one mole is 3.32×10×_24.so number of nucleon present in 1 neutrons= 3.32×10×-23÷3.32×10×_24=10 neutrons in one atom.so no of neutrons present in 2 atom=10×2=20 neutrons