3.50 moles of many mango seeds = 2.107.10²⁴ mango seeds
Further explanation
A mole is a unit of many particles (atoms, molecules, ions) where 1 mole is the number of particles contained in a substance that is the same amount as many atoms in 12 gr C-12
While the number of moles can also be obtained by dividing the mass (in grams) with the molar mass of element or molecule
With Avogadro's number
N = number of gas particles
No = Avogadro number (6.02.10²³)
n = number of moles