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A spherical ball of radius 7cm contains ...

`A` spherical ball of radius `7cm` contains `56%` iron. If density is `1.4 g//cm^(3)`, number of mol of `Fe` present approximately is :

A

`10`

B

`15`

C

`20`

D

`25`

Text Solution

Verified by Experts

The correct Answer is:
C
no. of mol `=((4)/(3)pir^(3)xx(56)/(100)xx1.4)/(56)`
`=(4)/(3)xx3.14xx(7)^(3)xx(1.4)/(100)~~20`
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