Question

calculate number of atoms in each of the following given atomic mass of i =127 a. 254 u of iodine (I) b. 254 g of iodine (i)

Answer 1

Answer:

Explanation :-

Given :-

Atomic mass of I = 127 u

To Find :-

No. of atoms in 254 u of Iodine

No. of atoms in 254 g of Iodine

Solution :-

( a )

No. of atoms = given mass / atomic mass

No. of atoms = 254/127 = 2 atoms.

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( b )

we know that,

Mass no. = atomic no.

Atomic no. of I = 127 u

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Therefore, Molar mass = 127 g

No. of moles = 254/127 = 2

Now,

No. of atoms = no. of moles × Avogadro's no.

No. of atoms = 2* 6.023 ,10'24

No. of atoms = 12.046*10'23

Explanation: