Nutrition and Growth of Bacteria (page 4) (This chapter has 6 pages) Â© Kenneth Todar, PhD Physical and Environmental Requirements for Microbial Growth The procaryotes exist in nature under an enormous range of physical conditions such as O2 concentration, Hydrogen ion concentration (pH) and temperature.
In a double replacement reaction parts of two compounds switch places to form two new compounds. Two reactants yield two products. For example when silver nitrate combines with sodium chloride, two new compounds--silver chloride and sodium nitrate are formed because the sodium and silver switched places.
Chemicals or substances change converting to one or more other substances, and these changes are called chemical reactions. At the molecular level, atoms or groups of atoms rearrange resulting in breaking and forming some chemical bonds in a chemical reaction.