Mass number

Wikipedia se

Hian jaao: navigation, khojo

Atom ke wajan jaada kar ke proton aur neutron se banaa rahe hae.

Ii vigyan stub hae. Aap iske barraa kar ke Wikipedia ke madat kare saktaa hae.

"http://hif.wikipedia.org/w/index.php?title=Mass_number&oldid=179828" se lawa gais hae