The mass of solid [tex]\rm Ca(OCl)_2[/tex] needed is 2.64 mg.
Calcium hypochlorite is an inorganic compound whose chemical formula is [tex]\rm Ca(OCl)_2[/tex].
For this calculation, we will use stoichiometry
[tex]\rm 40 mg/L \times \dfrac{1l}{1000 mL} \times 50 mL\dfrac{1g}{1000 mg} \times \dfrac{1\;mol\;OCL^-}{51.452 g} \times \dfrac{1 mol Ca(OCl)_2}{2 mol OCl^-} \times 142.983 g Ca(OCl)_2/mol \times 0.95 \\\\= 2.64 \times 10^-^3 or \;2.64\;mg.[/tex]
Thus, the mass of solid [tex]\rm Ca(OCl)_2[/tex] needed is 2.64 mg.
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