Properties of Water

A water strider can skate along the top of a pond because....

• covalent bonds result in water cohesion (surface tension)

• hydrogen bonds result in water cohesion (surface tension)

• water striders have adapted to become lighter than water

• low surface tension of water

Answer explanation

Cohesion is where water molecules stick together because of hydrogen bonding.

Attractions between water molecules are called ....

• Covalent bonds

• Ionic bonds

• Polar bonds

• Hydrogen bonds

The attraction that causes water and other liquids to form drops on thin films is called ________________. This is also water’s ability to be attraction to other water molecules.

• adhesion
• capillary action
• cohesion
• surface tension

Answer explanation

Cohesion is where water molecules stick together because of hydrogen bonding.

Water is polar because...

• The unequal sharing of electrons gives the water molecule a slight negative charge near its oxygen atom and a slight positive charge near its hydrogen atoms.
• The molecule has two poles, at which the it is colder than other regions of the molecule.
• The unequal sharing of electrons gives the water molecule a slight negative charge near its hydrogen atoms and a slight positive charge near its oxygen atom.
• The water molecule is neutral.

Answer explanation

A bond created by the weak attraction of a slightly positive hydrogen atom to a slightly negative portion of another molecule is called ..........

• polar molecule
• solution
• adhesion
• hydrogen bond

Answer explanation

Hydrogen bonds are due to water molecules being polar.

Tags

NGSS.HS-ESS2-5

The tendency of molecules of the same kind to stick to one another is called .....

• cohesion
• adhesion
• solution
• polar molecule

Answer explanation

Co means together, so cohesion means water molecules sticking together.

A molecule in which opposite ends have opposite electric charges is called .....

• cohesion
• polar molecule
• hydrogen bond
• solution

Answer explanation

It is a polar molecule because of the unequal sharing of electrons creating a slightly negative pole and a slightly positive pole in the same molecule.

Which properties of water are helpful for aquatic organisms? (3)

• Ice is less dense than liquid water so forms an insulating layer on ponds and polar seas/oceans

• Having a high specific heat capacity stops the temperature of ponds, lakes, and oceans fluctuating too much over a short period of time

• High latent heat of vaporization means ponds, lakes, seas, and oceans don't lose too much water on extremely hot days

• Hydrogen bonds make it easier for fish to swim

• Being a polar molecule allows electric eels to become charged up quicker

Tags

NGSS.MS-ESS2-4

NGSS.MS-LS2-3

Water is a universal solvent because...

• it can be found anywhere

• it freezes when it gets cold

• it floats when frozen

• it dissolves most substances

Answer explanation

A solvent is a liquid that allows other substances to dissolve into it. Remember, most chemical reactions happen in solution (dissolved in a liquid).

Tags

NGSS.MS-ESS2-4

NGSS.MS-PS1-2

Which characteristic of water will allow a paperclip to remain floating on the surface of water?

• adhesion

• surface tension

• solvent properties

• non-polar

Answer explanation

Surface tension is where the force of the hydrogen bonds push up supporting the weight of the paper clip. As soon as the hydrogen bonds are broken, the paperclip will sink.