Tin

Location:  Group 14, Period 5
Atomic Weight:  118.710
Coordination Number:  4, 5, 6, 7, 8
Chemical Form in Solution:  Sn(OH)_xF_y^2-
(coordination numbers in green are observed less frequently)

Intended Use: For the calibration of analytical instruments and validation of analytical methods as appropriate.

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 and dilute HF / HNO₃. Avoid neutral to basic media. Unstable at ppm levels with metals that would pull F^- away (i.e. - do not mix with Alkaline or Rare Earths or high levels of transition elements unless they are fluorinated). Stable with most inorganic anions, provided it is in the chemical form shown above.

Stability:  2-100 ppb levels stable (alone or mixed with all other metals that are at comparable levels) as the Sn(OH)_xF_y^2- for 1 year in 1% HNO₃ / LDPE container. 1-10,000 ppm single element solutions as the Sn(OH)_xF_y^2- are chemically stable for years in 2-5% HNO₃ / trace HF in a LDPE container.

Sn Containing Samples (Preparation & Solution):  Metal (soluble in HF / HNO₃ or HCl); Oxides - SnO (soluble in HCl), SnO₂ - very resistant to all acids including HF (fusion with equal parts of Na₂CO₃ and S is soluble in water or dilute acids as the thiostannate); Alloys (treat first 0.1 g with 10 mL conc. H₂SO₄ to boiling until the alloy disintegrates and nearly all of the Sulphuric acid is expelled. Then add 100 mL O₂ free water and 50 mL of conc HCl or transfer to a plastic container and add 1 mL HF, in either case, warming gently to bring about solution); Organic Matrices (volatility and precipitation of the insoluble stannic oxide are problems -- because these preparations are prone to error, we recommend you contact our technical staff at sales@esslab.com or tel:01702 555577 and we'll provide you with the necessary data for your specific sample type).