The mass of lithium is [tex]3.5[/tex]g
Lithium react with water to form the lithium hydroxide.
the following chemical reaction will be :
[tex]Li(s)+H_{2}O(aq)- > LiOH(aq)+\frac{1}{2}H_{2}(g)[/tex]
the number of moles of 12g lithium hydroxide is
mole=[tex]\frac{GIVEN MASS}{MOLAR MASS}[/tex]
molar mass of LiOH is = 24g
given mass =12g
mole=[tex]\frac{12}{24}[/tex].
mole=[tex]0.5[/tex].
On comparing the stoichiometry of the given reaction
Mole of Li = moles of LiOH,
then moles of Li=[tex]0.5g[/tex].
mass of Li=0.5 x molar mass of li.
mass of Li=[tex]0.5[/tex]x[tex]7[/tex]=[tex]3.5g[/tex].
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