UNIT II

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

What two elements make up water?

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

Tags

NGSS.MS-PS1-1

molecule in which opposite ends have opposite electric charges

• cohesion
• polar molecule
• hydrogen bond
• solution

Tags

NGSS.MS-PS1-1

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

The reason the water balloon did NOT pop while held over a flame is water's _________.

• Less dense than air.
• Hydrogen bonds between water molecules.
• polarity.
• high specific heat capacity.

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

The fact that ice floats on liquid water is due to the fact that water's solid is ___________ than it's liquid form

• less polar
• more polar
• less dense
• more dense

Tags

NGSS.MS-PS1-4

Water striders can walk across the surface of calm water. Their feet push the surface of the water down slightly, but they do not break the surface. Why?

• The insects are light enough so 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 insect’s 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 general definition of cohesion is the attraction of:

• particles of the same substance
• particles of a different substance
• particles of both the same and different substances
• particles of neither the same or different substances

Which term refers to water having partial positive and a partial negative charge?

• cohesion
• surface tension
• polarity
• adhesion