Question

answer it fast chemistry ques​

Answer 1

$\large\underline{\blacksquare \: \: {\rm Point \; to \: Remember-}}$

An element is represented by ${\sf _zX^A}$

X = Symbol of element

Z = Atomic number = no. of proton = no. of ${\sf e^-}$ (if atom is neutral )

A = Mass number = no. of neutron + Atomic no.

$\large\underline{\bigstar \: \: {\sf Question-}}$

Give the complete symbols for ions with the following numbers of subatomic particles :

$\bullet{\bf 15\:protons, \: 16\: neutrons,\: and \: 18\: electrons }$

$\large\implies{\sf Answer - P^{-3}}$

Explanation :

$\implies{\sf _{15}P^{31}}$

$\implies{\sf no. \: of \: proton \; is \: = 15}$

$\implies{\sf no. \: of \: neutron \: is = 31-15 }$

$\implies{\bf 16}$

$\implies{\sf no. \; of \: electron = 15+3}$

$\implies{\sf 18}$

$\bullet{\bf 56\: proton, 82\: neutron, \: and \: 54\: Electron}$

$\large\implies{\sf Answer - Ba^{+2}}$

Explanation :

$\implies{\sf _{56}Ba^{138} }$

$\implies{\sf no. \: of \: proton =56}$

$\implies{\sf no. \; of \: neutron = 56-138}$

$\implies{\sf 82 }$

$\implies{\sf no. \: of \: electron = 56-2 }$

$\implies{\sf 54}$

$\bullet{\bf 13\: proton , 14\: neutron , \: 10\: electron }$

$\large\implies{\sf Answer - Al^{+3} }$

Explanation :

$\implies{\sf _{13}Al^{27}}$

$\implies{\sf no. \; of \: proton = 13}$

$\implies{\sf no. \; of \: neutron = 27-13 }$

$\implies{\sf 14 }$

$\implies{\sf no . \: of \: electron = 13-3}$

$\implies{\sf 10 }$