Study Guide (Academic)
WATER TEST
Test Dates: A day (_______) B day (______)
Item # ___________
Name: _________________________________
Science/Key/ Block # _________________
Date: ____________________________
DENSITY
1. What two measurements would you have to take to solve for the density of water, and what laboratory
equipment would you need?
Equipment choices: (mass, temperature, time, volume, length)
Answer: _____mass_____ and ________volume_____________
Laboratory equipment choices: (TBB, thermometer, metric ruler, graduated cylinder)
Answer: _______tbb________ and _____graduated cylinder__________
2. What is the density of liquid water…
(choices - .0006 g/mL; 1 g/mL; 0.92 g/mL)
a) at as a liquid?
__1 g/ml________
b) at as a solid? ___.92g/ml____________
c) at as a gas? ____.006g/ml____________
3. Why does ice float on liquid water? (In other words, why is ice less dense than liquid water?
(complete sentence required)
When liquid freezes the movement slows down causing molecules to separate. Air is
trapped in the space thus decreasing density and allowing ice to float.
4. Which of the following substances would sink in water? (circle the answer)
aluminum , density 2.7 g/mL
oil, density .8 g/mL
oak wood, density 0.8 g/mL
5. Explain why two molecules of water “stick” to each other?
Because water is polar (positive and negative) which allows it to be attracted to other polar molecules like a
magnet.
WATER MOLECULE
H – 0N & 1P
6.
In the box to the right Draw the Bohr model of the water molecule.
Make sure you use a symbol to represent for oxygen & hydrogen:
 Electrons
 Protons
 neutrons
 positive and negative
 circle and label the type of bonds
+
+
8p
8n
Covalent bond
7.
What is a polar molecule? (complete sentence required)
--
A polar molecule is when each end of the molecule has opposite charges.
8.
The fact that water is a polar molecule causes water to have what properties? (list 6)
9.
Universal Solvent
Cohesive
Adhesion
Surface Tension
Capillary Action
Heat Sink
Draw a model of the water molecules as they would exist as water vapor, liquid water, and solid water.
Gas
Liquid
Solid
WATER EXISTING AS A SOLID LIQUID OR GAS (9 -15)
Word bank: (words may be used once, multiple times or not at all) Some questions can have 2 answers.
o
100 C
solid
liquid
gas
0 oC
evaporation
condensation
_____Gas_____ 10. Which state of water would have the lowest density?
__Evaporation / 100oC 11. When water evaporates?
__Solid_________
12. The state of matter that has the least amount of energy(movement)
__Evaporation / _100oC ___13. When water boils?
________0oC _______________14. The temperature that water changes from a liquid to a solid.
_______100oC _______________15. The temperature that water changes from a solid to a liquid.
______Liquid____________16. Which state of water would have the highest density?
PROPERTIES OF WATER (17-27)
Determine what property of water is being mentioned. You will use the words more than once
Word bank: cohesion - - adhesion - - surface tension – capillary action - - universal solvent
_____A_____17. Water drops stick to the inside of your water bottle.
_____C_______18. Water molecules are attracted to each other so rain drops form in the atmosphere.
___C.A._______19. Water climbs the tubes inside the trunk of a tree so that the tree tops receive water.
__S.T.________20. A paper clip is able to float on the surface of water if it is placed very carefully.
__U.S.______21. Our oceans consist of salt water.
___C.A.______22. Water is absorbed up the holes in a sponge or paper towel.
__C & A or S.T__23. Water creates a meniscus inside a graduated cylinder.
___U.S._____24. Our blood dissolves and transports sugars and other vital chemicals throughout our body.
___S.T.______25. Fish eggs rest on top of the water.
___S.T.______26. A water strider is capable of “walking on water.”
___C.A._______27. Oil in a lantern rises up the wick.
28. In water, what happens to the movement and arrangement of the molecules in a solid, liquid, and gas.
Liquid water:
Gas/Steam:
Ice:
-Molecules are close together
-Molecule move slowly
DENSITY = 1.0 g/mL
Water
-Molecules are widely
separated .
-Molecule move around
freely
-Molecules move rapidly
DENSITY=0.0006 g/mL
Gas
-When water freezes, molecules move
away from each other and expand.
-Molecules move slightly.
-When ice forms it floats it is less dense
than water.
3
DENSITY = .92 g/cm
Ice
29. Give three reasons water is unique. (complete sentence required)
-Water is Polar
-Water is a universal solvent
-Water can creep up thin tubes (defy gravity, capillary action)
30. What is solubility and what is a solution? (complete sentence required)
Solubility is the ability of a solvent (water) to dissolve a solute (solid) to create a solution.
In a solution there is only a physical reaction …..not chemical Example salt and water.