Question

Calculate the number of atom present in 640u helium

Answer 1

Answer:

Molar mass of He = 4 u

Given mass of He = 64 u

Number of moles present = Given mass / Molar mass

= 64u / 4u = 16 moles

Number of atoms present(n)= Avogadro's constant * Number of moles

n = 6.022 * 1023 * 16 = 96.350 * 1023

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