Carius method (halogen and sulfur estimation) (%Halogen = (Atomic mass of X × mass of AgX precipitate) / (Molar mass of AgX × mass of)

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%Halogen = (Atomic mass of X × mass of AgX precipitate) / (Molar mass of AgX × mass of compound) × 100

What each symbol means

SymbolWhat it stands for
WMass of organic compound (g)
A_XAtomic mass of halogen (Cl=35.5, Br=80, I=127)
M_AgXMolar mass of AgX (AgCl=143.5, AgBr=188, AgI=235)
m_AgXMass of silver halide precipitate (g)

When to use this

Compound heated with fuming HNO₃ in sealed thick-walled glass tube (Carius tube) at ~570 K. Complete oxidation of organic matter. Halogen precipitated as AgX; sulfur as BaSO₄.