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.
sugar+water= water with sugar in it = no new substances = physical reaction. Physical Reactions (Also known as a Physical Change). A physical reaction takes place when two substances meet, and only the form changes, but not the composition. For example, when sugar and the water ar. e mixed together, nothing new is created.