Biogeochemical Cycles What is a biogeochemical cycle?
Describe/Define the 3 cycles below in detail and explain the consequences of imbalance for each one:
Water/Hydrologic cycle
Understand effects and issues associated with too much or too little water
What 2 phases of the cycle most affect the imbalance of each of these?
Nitrogen cycle
Explain the effect of runoff on algal bloom
Explain how runoff adds excess nutrients to the oceans
Explain how atmospheric nitrogen becomes ammonia
Carbon cycle
Understand the significance of dissolved carbon in building corals

The atomic radius of sodium is 186 pm and of chlorine is 100 pm. the ionic radius for na+ is 102 pm and for cl– is 181 pm. in going from na to cl in period 3, why does the atomic radius decrease while the ionic radius increases? a. the inner electrons in the sodium cation shield its valence electrons more effectively than the inner electrons in the chloride anion do. b. the inner electrons shield the valence electrons more effectively in the chlorine atom than in the chloride anion. c. the outermost electrons in chloride experience a smaller effective nuclear charge than those in the sodium cation do. d. the outermost electrons in chloride experience a larger effective nuclear charge than those in the sodium cation do. e. monatomic ions are bigger than the atoms from which they are formed.

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

When water dissolves sugar, which process is not involved? o dissociation o hydration o surface area of the solute increases sa