Question

silicon has atomic mass of 28. how many atoms are present in 56gm of it??? please explain

Answer 1

Here Is Your Ans ⤵

****

➡Mole = sample mass / atomic mass

➡Mole = 56 / 28

➡Mole = 2

Hence , 2 atoms are present in 56gm of Silicon

***

Follow Me

Answer 2

Average atomic weight of Silicon, Si atom is

28.0855

units.

We know from Mole concept that 1

mole is

6.022×10^-23

of anything. This number is called Avogadro's number.

Also that 1

mole of Silicon weighs

28.0855g.

Therefore,

28.0855

g of Silicon contains

6.022×10^-23

of Silicon atoms.3.5

g of Silicon contains number of atoms

=

6.022×10^-23/28.0855×3.5

=7.505×10^22

atoms. (rounded to third place of decimal)