Solubility
Polarity
Heavy Metals
Pressure
Acids + Bases
100
What does it mean if a solution is saturated?
The maximum amount of a substance that will dissolve in a certain AMOUNT of water at a given TEMPERATURE
100
What is a polar molecule?
A molecule that has a partial positive and a partial negative charge, like water.
100
Why are heavy metals called "heavy"?
They have a high atomic weight.
100
When the temperature increases, what happens to the solubility of gas?
The solubility decreases.
100
What do we use to measure the acidity or alkalinity of a solution?
The pH scale.
200
Why does salt dissolve in hot tea but not in cold tea?
Because sugar is more soluble at higher temperatures.
200
What part of a water molecule is attracted to a K+ ion and why?
The oxygen atom- it has a partial negative charge.
200
What is a symptom of lead poisoning?
Abdominal pain, confusion, headache, anemia, irritability, and in severe cases seizures, coma, and death.
200
When pressure increases, what happens to the solubility of gas?
The solubility increases.
200
What does pH measure?
pH is the "Power of Hydrogen". It measures the concentration of [H+] ions in a solution.
300
Which solvent is MOST soluble at 20 degrees C?
NaClO3
300
What part of a water molecule is attracted to Br-?
The hydrogen atoms- they have a partial positive charge.
300
What is a symptom of mercury poisoning?
Sensory impairment (vision, hearing, speech), disturbed sensation and a lack of coordination.
300
How do SCUBA divers get "the bends"?
Nitrogen gas dissolves in their blood, and can expand in their blood stream if they come to the surface too quickly- causing heart attacks, stroke, and general discomfort.
300
List three negative effects of inappropriate pH levels on aquatic organisms
Too LOW- fish egg development is impaired, increase the concentrations of metal ions Too HIGH- alkaline solutions dissolve skin and scales
400
Which solute is LEAST soluble at 80 degrees C?
NaCl
400
What is the concentration of a 1% salt solution in ppm?
1% of 1,000,000 is 10,000 ppm.
400
Someone could be exposed to lead through...
Pottery, automobile electrical storage batteries, pesticides, cooking vessels, paint
400
Why does warm cola produce more fizz than cold soda?
Carbon dioxide does not dissolve as well in a warm solvent, so the gas tries to escape when the can is opened.
400
A pH of 2.7 is ___
Acidic
500
Why does salt dissolve in water but not in oil?
Salt is a polar solute, and water is a polar solvent- "like dissolves like"
500
If a solution has 4.5 g NaCl in 495.5 g water, what is the percent concentration of NaCl ?
0.90%
500
Someone can be exposed to mercury through...
"silent" light switches, thermometers, thermostats, mercury-vapor street lamps, fluorescent light bulbs, paints, and by eating contaminated seafood.
500
What is gas-bubble trauma in fish?
When the water is supersaturated with DO and nitrogen- bubbles form in fish's bodies and kills them.
500
What ion is found in bases?
Hydroxide ions, or [OH-]
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