Water Consistent

Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon?

• Water is an acid.
• Water is a versatile solvent.
• Water has a high heat capacity.
•  Water acts as a buffer.

Water is often called the "universal solvent" because many substances can be dissolved in water. What property of water allows it to be such a versatile solvent? 

• Purity

• Polarity and cohesion

• High heat capacity

• Expansion upon freezing

 Small insects can walk across the surface of calm water. Their feet push the surface of the water down slightly, somewhat like a person walking across a trampoline, but they do not break the surface. What is the best explanation for why this happens?

• The insects are light enough so that they do not break the hydrogen bonds holding the water molecules together
• The insects actually use their wings to hover slightly above the water's surface and they only skim it with their feet
• The insects' feet are non-polar, so they are repelled by the polar water molecules and are pushed away from the water's surface
• The insects are small enough to see the individual water molecules, so they are able to step carefully from one molecule to the next

Tags

NGSS.MS-PS2-5

A florist places a bouquet of white carnations in water containing blue dye. After a time, the flowers turn blue. What process helped the carnations to change color?

• Specific heat 
• Surface tension
• Cohesion and adhesion of water molecules 
• Formation of covalent bonds between hydrogen and oxygen molecules

Water makes up approximately 60% of the human body and plays a vital role in regulating body temperature. Which property of water makes it good at regulating temperature?

• Water is a good solvent.
• Water exhibits strong cohesion.
• Water has an unusual crystalline structure.

• Water has a high capacity for heat.

 Many fish and aquatic plants can survive a cold winter because the layer of ice that forms at the top of the lake insulates the water below and prevents the lake from freezing solid. What unique property of water contributes to this effect? 

• Water absorbs heat when it evaporates and forms a gas 
•  Water expands and becomes less dense when it freezes.
• Water molecules completely separate into ions in solutions.
•  Water forms hydrogen bonds with ions and other polar substances. 

Tags

NGSS.HS-ESS2-5

The charge of oxygen in a water molecule is ______________.

• Negative

• Neutral

• Positive

• Balanced

What type of bond is indicated by the #1?

• Covalent bond

• Oxygen bond

• Hydrogen bond

• Triple bond

What causes water to be polar?

• The oxygen end is negative, hydrogen ends are positive

• The hydrogen ends are negative, the oxygen end is positive

• Both oxygen and hydrogen ends are positive

• Both hydrogen and oxygen ends are negative

A(n) --- is a substance with a pH greater than 7, while a(n) --- is substance with a pH less than 7.

• Base ; Acid

• Acid : Base

• Buffer : Solute

• Water : Solvent