Skip to main content
Chemistry LibreTexts

Appendix 08: Recommended Primary Standards

  • Page ID
    6644
  • All compounds should be of the highest available purity. Metals should be cleaned with dilute acid to remove any surface impurities and rinsed with distilled water. Unless otherwise indicated, compounds should be dried to a constant weight at 110 oC. Most of these compounds are soluble in dilute acid (1:1 HCl or 1:1 HNO3), with gentle heating if necessary; some of the compounds are water soluble.

    Element Compound FW (g/mol) Comments
    aluminum Al metal 26.982 -
    antimony Sb metal 121.760 -
    - KSbOC4H4O6 324.92 prepared by drying KSbC4H4O6•1/2H2O at 110oC and storing in a desiccator
    arsenic As metal 74.922 -
    - As2O3 197.84 toxic
    barium BaCO3 197.84 dry at 200 oC for 4 h
    bismuth Bi metal 208.98 -
    boron H3BO3 61.83 do not dry
    bromine KBr 119.01 -
    cadmium Cd metal 112.411 -
    - CdO 128.40 -
    calcium CaCO3 100.09 -
    cerium Ce metal 140.116 -
    - (NH4)2Ce(NO3)4 548.23 -
    cesium Cs2CO3 325.82 -
    - Cs2SO4 361.87 -
    chlorine NaCl 58.44 -
    chromium Cr metal 51.996 -
    - K2Cr2O7 294.19 -
    cobalt Co metal 58.933 -
    copper Cu metal 63.546 -
    - CuO 79.54 -
    fluorine NaF 41.99 do not store solutions in glass containers
    iodine KI 166.00 -
    - KIO3 214.00 -
    iron Fe metal 55.845 -
    lead Pb metal 207.2 -
    lithium Li2CO3 73.89 -
    magnesium Mg metal 24.305 -
    mercury Hg metal 200.59 -
    molybdenum Mo metal 95.94 -
    nickel Ni metal 58.693 -
    phosphorous KH2PO4 136.09 -
    - P2O5 141.94 -
    potassium KCl 74.56 -
    - K2CO3 138.21 -
    - K2Cr2O7 294.19 -
    - KHC8H4O2 204.23 -
    silicon Si metal 28.085 -
    - SiO2 60.08 -
    silver Ag metal 107.868 -
    - AgNO3 169.87 -
    sodium NaCl 58.44 -
    - Na2CO3 106.00 -
    - Na2C2O4 134.00 -
    strontium SrCO3 147.63 -
    sulfur elemental S 32.066 -
    - K2SO4 174.27 -
    - Na2SO4 142.04 -
    tin Sn metal 118.710 -
    titanium Ti metal 47.867 -
    tungsten W metal 183.84 -
    uranium U metal 238.029 -
    - U3O8 842.09 -
    vanadium V metal 50.942 -
    zinc Zn metal 81.37 -

    Sources: (a) Smith, B. W.; Parsons, M. L. J. Chem. Educ. 1973, 50, 679–681; (b) Moody, J. R.; Greenburg, P. R.; Pratt, K. W.; Rains, T. C. Anal. Chem. 1988, 60, 1203A–1218A.