**Given :** atomic mass of I=127 u

**A. 254 u of iodine (I) **

Formula : number of atoms = \(given \space atomic \space mass \space of \space element\over atomic \space mass \space of \space element\)

\(\therefore \space ={254\over 127}\)

**=2 atoms **

**254 u of iodine (I) consist of 2 atoms of I **

**B. 254 g of iodine (I)**

we know the Molar mass of iodine which is 127 g

Formula :: no of moles =\(given\space mass\over molar \space mass\)

\(\therefore\space = {254\over 127 }=2\) moles

therefore , number of atoms = n× Avogadro's number

=2\(\times 6.022\times 10^{23}\) atoms =\(1.2044\times 10^{24} atoms\)

**254 g of iodine (I) consist of \(1.2044\times 10^{24} atoms\)**