11. The number of functional groups on TNT influences the ability to adsorb into soil. 12. In aquaria, zeolites can be used to adsorb ammonia and other nitrogenous compounds. 13. 3?molecular sieves do not adsorb molecules whose diameters are larger than 3 ? 14. Traps are gradually poisoned by SO x which adsorbs more strongly than NO x. 15. The hydrophobic contaminants adsorb to these supports, improving permeability in sand and soil. 16. One is when arsenate is reduced to arsenite which adsorbs to iron oxides less strongly. 17. Next the water is run through a tank containing activated charcoal to adsorb organic contaminants. 18. A variety of methods exist to adsorb these antibodies from the test sample before hemagglutination. 19. Selectivity The calculated ability of an adsorbent to preferentially adsorb one gas over another gas. 20. Soil biota can treat waste by transforming it; soil colloids can adsorb the waste material.