NAME:
Mods:
“Water World”
You may highlight the answers to most of the questions in the packet (number them though!).
For questions that involve writing or solving equations, I left space for that. Any bulleted and italicized
questions are extra thought questions, and you may need the internet’s help with those!
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8.
What is water the foundation of?
What type of bond is each Oxygen-Hydrogen bond in the water molecule?
What shape is the water molecule? Because of this, what is the water molecule?
What is a hydrogen bond?
What are 7 unique physical properties of water caused by hydrogen bonding?
Why are CH4, NH3, and CO2 gases at room temperature while water is a liquid?
What is the difference between water molecules within a sample and those at the surface?
What is surface tension? Why is water’s higher than most other liquids?
 Watching the Olympics, you notice that during the diving competition there are bubblers
that create large amounts of bubbles where the divers enter the water. Why do you
suppose this is? I bet it might have something to do with surface tension!
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What is evaporation? What do we call a liquid that evaporates easily?
What is vapor pressure? Why is water’s low?
What is the boiling point of a liquid defined as?
 If water boils at 100 ºC at sea level, what temperature will water boil at in Denver,
Colorado (“The Mile high City”): 100 ºC, less than 100 ºC, or greater than 100 ºC?
 Why are there “High Altitude” cooking instructions for some products?
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What is the heat of vaporization?
Why do we feel “cold” when a volatile liquid comes in contact with our skin?
What do we call the reverse of vaporization?
Explain why steam burns can be so harmful.
What is specific heat (c)?
If you have 256 g of water, 256 g of iron and 256 g of sand, calculate how many Joules of
energy it will take to heat the samples from 20 ºC to 99 ºC. See the difference!
256 g water
256 g iron
256 g sand
18.
Calculate how much energy is released when 875 g of copper and 875 g of water cool
down from 92 ºC to 25 ºC. See the big difference!!!
875 g copper
875 g water
19.
A piece of metal weighing 722 g is heated up. Its initial temperature is 23 ºC, and 30
minutes later it is 249 ºC. If the metal absorbed 73,280 Joules of energy, what is the
specific heat of the metal, and, what metal is it?  Use the back of your Periodic Table! 
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21.
When a liquid sample freezes to become a solid, what normally happens?
Water, of course, is different! Describe what happens as water starts to freeze
(from 4 ºC to 0 ºC), and what this ultimately leads to!
 Comparing the density of water and ice, what percentage of an ice cube would be found
below the surface of water, and what percentage would be found above?
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What important consequence does the fact that ice floats have for living organisms?
Why is water known as the “universal solvent”?
Water samples containing dissolved substances are known as what?
In a solution, what do we call the dissolved particles and what do we call what is
doing the dissolving?
What substances can dissolve in water? Why, and How?
What do we call the process when a solute dissolves? What if water is the solvent?
How do nonpolar solutes dissolve in nonpolar solvents?
What is the difference between electrolytes and nonelectrolytes?
What types of compounds are electrolytes and nonelectrolytes?
What is the main difference between a strong and weak electrolyte?
Classify the following compounds as a strong electrolyte, a weak electrolyte, or a
nonelectrolyte: yes, you can write strong, weak or non! Lazy…
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HCl
fructose
KBr
butane
HNO3
cooking oil
ethanol
LiF
citric acid
NH3
NaI
CH4 (methane)
Mg(OH)2
CCl4
PbCl2
33.
Write the equation to show how solid sodium chloride becomes aqueous.
34.
Write the equation to show how solid aluminum sulfate becomes aqueous.