Unit 1 and 2 Review

What two elements make up water?

• Helium and oxygen
• Hydrogen and oxygen
• helium and carbon
• oxygen and carbon

Tags

NGSS.MS-PS1-1

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

Why does ice float?

• As water freezes, it expands and its density decreases.
• As water freezes, it takes up more hydrogen from the atmosphere, causing it to have a greater buoyancy.
• As water freezes, air becomes trapped between the hydrogen bonds of water molecules.
• As water freezes, it takes up more oxygen from the atmosphere, causing it to have a greater buoyancy.

Tags

NGSS.MS-PS1-4

Water is a universal solvent because it...

• It can be found anywhere
• It freezes when it gets cold
• floats when frozen
• Dissolves most substances

Tags

NGSS.MS-PS1-2

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.

Tags

NGSS.MS-PS3-4

 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

The tightness across the surface of water that enables paper clips to float is ____________.

• adhesion
• capillary action
• surface tension
• polarity

Which statement explains why water molecules stick together?

• both sides are negative
• one side has a positive charge and the other side has a negative charge
• one side has a negative charge adn the other side has a neutral charge
• both sides are positive

Tags

NGSS.HS-PS1-3

NGSS.HS-PS2-4

When a molecule has an opposite electrical charge on each end, it is known as what?

• cohesion
• polar molecule
• hydrogen bond
• solution

Tags

NGSS.MS-PS1-1

When water molecules stick easily to other water molecules, this is called what?

• cohesion
• adhesion
• solution
• polar molecule