Sulfur
Location: Group 16, Period 3
Atomic Weight: 32.066
Coordination Number: 6
Chemical Form in Solution: (O)2S(OH)2
Storage & Handling:
Keep tightly sealed when not in use. Store and use at 20 ± 4°C. Do not
pipet from container. Do not return portions removed for pipetting to
container.
Chemical Compatibility: Soluble in HCl, HNO3, H3PO4, and HF aqueous matrices, water, and NH4OH.
Stable with all metals and inorganic anions at low to moderate ppm
levels under acidic conditions, except Ba, Pb, Ca, and to a lesser
extent Sr.
Stability: 2-100 ppb levels - stability unknown - in 1% HNO3 / LDPE container. 1-10,000 ppm solutions chemically stable for years in LDPE container.
S Containing Samples (Preparation & Solution):
We most often get questions about the determination of S in rocks,
silicates and insoluble sulfates (the finely powered sample is fused in
a Pt0 crucible with 6 times its weight of Na2CO3 + 0.5 grams KNO3. The fuseate is extracted with water. Any BaSO4 present in the sample is transposed by the carbonate fusion to the BaCO3, which is left behind in the water-insoluble residue. If PbSO4 is present, the fuseate should be boiled with a sodium carbonate saturated with CO2 solution for 1 hour or more. The PbSO4
will be transposed to the water insoluble carbonate which can be
filtered off. Boiling the fuseate with a saturated carbonate solution
is good insurance for samples containing Ba, Sr, and Ca. The Ba, Pb,
Sr, and Ca free filtrate can be acidified and measured by ICP).
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