Question

A silicon chip used in an integrated circuit of a microcomputer has a mass of 5.68 ,mg. How many silicon atoms are present in this chip ? (Atomic mass of Si = 28.08)

• A. $6.02\times {10}^{23}$
• B. $5.68\times {10}^{23}$
• C. $1.22\times {10}^{20}$
• D. $11.36\times {10}^{23}$

Answer 1

The correct option is C $1.22\times {10}^{20}$

As we know,
no of mole = wt given/mol wt
so no of atoms $=n\times N_A=(5.68\times {10}^{-3}/28.08)\times N_A$ = $1.22\times {10}^{20}$