Question

properties of water test review worksheet

1. what elements are important to all living things?
2. the hydrogen and oxygen atoms in a water molecule are held together by
3. the electrons in a water molecule are not shared equally creating a
4. hydrogen bonds form between adjacent water molecules because the charged hydrogen end of one water molecule attracts the charged oxygen end of another water molecule.
5. water molecules stick to other water molecules. this property is called
6. water molecules stick to other materials due to its polar nature. this is called
7. creates the skin - like surface formed due to the polar nature of water.
8. what property of water causes ice to float?
9. a molecule that has a partial charge on one end and a partial positive charge on the other end is called
10. unique properties of water include: dense as a solid and retains large amounts of heat.
11. the amount of heat needed to raise or lower 1g of a substance 1 degree c is called
12. what property of water causes capillary action?
13. draw two water molecules and identify the following:

a. the molecular formula (how would a chemist write \water\)
b. the bonds between 2 water molecules
c. the bonds within the water molecule (between hydrogen and oxygen).
d. label the positively and negatively charged portions of the molecule.

Explanation:

1. Carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur are important elements for all - living things.
2. Covalent bonds hold hydrogen and oxygen atoms in a water molecule together.
3. Unequal electron - sharing creates a polar molecule.
4. The positively charged hydrogen end of one water molecule attracts the negatively charged oxygen end of another water molecule.
5. Cohesion is the property of water molecules sticking to other water molecules.
6. Adhesion is when water molecules stick to other materials due to its polar nature.
7. Surface tension creates the skin - like surface due to the polar nature of water.
8. Ice floats because water is less dense as a solid.
9. A molecule with a partial negative charge on one end and a partial positive charge on the other end is called a polar molecule.
10. Water is less dense as a solid and has a high heat capacity.
11. The amount of heat needed to raise or lower 1g of a substance 1 degree C is called specific heat.
12. Cohesion and adhesion cause capillary action.
13. a. The molecular formula of water is $H_2O$. b. The bonds between 2 water molecules are hydrogen bonds. c. The bonds within the water molecule (between hydrogen and oxygen) are covalent bonds. d. The oxygen end is negatively charged and the hydrogen ends are positively charged.

Answer:

1. Carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur
2. Covalent
3. Polar
4. Positively; negatively
5. Cohesion
6. Adhesion
7. Surface tension
8. Less density as a solid
9. Negative; polar molecule
10. Less
11. Specific heat
12. Cohesion and adhesion
13. a. $H_2O$

b. Hydrogen bonds
c. Covalent bonds
d. Oxygen - negative; Hydrogen - positive