Question

Calculate the mass of a) 10^20 atoms of nitrogen atom​

Answer 1

Answer:

1.4 x 10^21 u    or    2.324 x 10^(-3)grams

Explanation:

Mass of 1 atom of Nitrogen = 14u

mass of 10^20 atoms of nitrogen = 14u x 10^20 = 1.4 x 10^21 u

mass of 10^20 atoms of nitrogen in grams

                          = (1.4 x 10^21) x (1.66 x 10^(-24)) g

                          = 2.324 x 10^(-3) g

[∵ 1 u = 1.66 x 10^(-24) grams ]  

hope it helps :))

Answer 2

2.2 × 10⁻³ g      

Explanation:

1 mole = 6.022 × 10²³ atoms

x mole = 10²⁰ atoms

x =  10²⁰/  6.022 × 10²³

x =  1.66 × 10⁻⁴ moles

mass = number of moles × molecular mass

         = 1.66 × 10⁻⁴ × 14

         = 2.2 × 10⁻³ g