CHEMISTRY & SOCIETY TEST: WATER UNIT SECTION C

NAME______

DATE______PERIOD_____

MATCHING

___1.Covalent/Molecular compounda) Heavy metal responsible for the term “Mad as a hatter”

___2.H2SO4b) A base

___3.Mercuryc) Describes a solution in which no more solute can dissolve

___4.Polyatomic iond) Heavy metal found in tobacco

___5.MgOHe) Heavy metal previously found in gasoline

___6.Saturatedf) Metal bonded to non-metal

___7.Leadg) Describes a solution which may dissolve more solute

___8.Unsaturatedh) An acid

___9.Ionic compoundi.) Non-metal bonded to non-metal

___10.Cadmiumj.) Group of atoms that act as a unit and share a charge

SHORT ANSWER / FILL-IN

  1. Provide the correct formula for what happens when the following elements get together: to form ionic compounds: (You will need to find the correct charges)
a)Ca with Cl______
b)Na with O______
c)Sr and F______
d)Ca and O______
  1. Name the following ionic compounds:

a) K2S ______b) Mg(OH)2 ______

c) AlCl3 ______d) MgS ______

e) Na(NO3)______f) CuO ______

  1. From the following names of ionic compounds, provide the correct formulas:

a)Iron (II) Chloride______

b)Beryllium Sulfide______

c) Potassium Oxide______

d) Calcium Sulfate______

  1. Provide the correct formula for the following Covalent compounds:

a) Diphosphorus trichloride______

b) Nitrogen tribromide______

  1. Provide the names of the following covalent compounds:

a)SO2______

b)PCl3______

c)N2O3______

  1. Provide 2 uses of lead (past or present):

______

  1. Provide 2 primary “essential metals” required by the human body:

______

  1. What physical form of mercury is most dangerous? ______
MULTIPLE CHOICE
  1. For gasses dissolving in liquids, an increase in temperature ______,

a) increases solubilityb) decreases solubility

c) does not change the solubilityd) makes solutions less concentrated

  1. For solids dissolved in liquids, an increase in temperature ______,

a) does not change the solubilityb) increases solubility

c) makes solutions less concentratedd) decreases solubility

  1. Which of these would most greatly increase aeration?

a) decreasing the amount of sewageb) lowering the pH of the water

c) placing a dam in the stream d) removing heavy metals from the water

e) raising the water level of the stream

  1. Photosynthesis affects the amount of dissolved oxygen in water. Which statement is true?

a)It increases D.O. during the day

b)It increases D.O. during the night and day

c)It decreases D.O. during the day

d)It decreases D.O during the night and day

  1. A pond is contaminated with a chemical that is a base. Which ion should be present in large amounts?

a) H+b) SO4-2c) Cd+d) OH-e) Ba+2

  1. On the pH scale Indian Lake has a pH of 5.9 and Lake Michigan has a pH of 8.2. From this information you can conclude:

a) Both lakes have base in themb) they are both pollutedc) Lake Michigan has acid in it

d) Indian Lake has acid in ite) Both lakes have acid in them

  1. Power companies often use river water to cool electric power plants. The water leaving the power plant would:

a)be cooler and have a lowered oxygen concentration

b)be cooler and have a higher oxygen concentration

c)be warmer and have a lower oxygen concentration

d)be warmer and have a higher oxygen concentration

SHORT ESSAYS and PROBLEMS
  1. Oops! In lab preparation, I accidentally spilled Iodine (I2) on my clothes. It turns out that Iodine is a non-polar compound. What would you suggest I use to try to remove it from my clothes, Ethanol (polar) or Turpentine (non-polar) – and WHY?

______

  1. If you were forced to drink water that contained either Lead, Mercury, Iron, or Cadmium, which one would you drink and why?

______

Use the Graph below to answer questions 28-29.

  1. If 60 grams of X is dissolved in 100 grams of water at 40 C, the solution is:

a) Unsaturatedb) Saturatedc) Supersaturated

  1. At 60 C, how many grams of X can be dissolved in 100 grams of water?______
  1. Find the percent concentration of a solution that has 0.008 grams lead ion in 15,000 grams of water.

______

  1. Express the concentration determined in problem 30 as ppm.

______

  1. The EPA threshold limit for lead in water for humans is 0.010 ppm; use the answer to question 31 to determine whether the water is safe to drink or not?

______

Things you might find helpful:

% solution = [ (g solute) / (g solution)] x 100% solution = pph

ppt = pph x 10ppm = pph x 10,000