Assume that the nucleus of the fluorine atom is a sphere of radius `5xx10^(-3)`cm. What is the density of matter in the nucleus?

Monjur Alahi

Assume that the nucleus of the fluorine atom is a sphere of radius `5xx10^(-3)`cm. What is the density of matter in the nucleus?
A. `6.02xx10^(23)g//mL`
B. `6.02xx10^(13)g//mL`
C. `12.02xx10^(23)g//mL`
D. `12.02xx10^(13)g//mL`


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Salim Ahmed Kawsar

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Correct Answer - B
Since almost, whole the mass of an atom is in the nucleus,
Mass of F nucleus = Mass of F atom
`=(19)/(6.02xx10^(23))g`
`=3.15xx10^(-23)g`
(At. Mass of F = 19)
Volume of nucleus `=(4)/(3)pir^(3)`
`=(4)/(3) xx(22)/(7)xx(5xx10^(-13)^(3)cm^(3)`
`=5.24xx10^(-37)cm^(3)`
Density `= ("Mass")/("Volume")=(3.15xx10^(-23))/(5.24xx10^(-37)cm^(3))`
`=6.02xx10^(23)gcm^(-3)=6.02xx10^(13)g//mL`

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