Biomolecules

What two elements make up water?

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

Tags

NGSS.MS-PS1-1

A insect like a water strider can skate along the top of a pond because:

• covalent bonds result in water cohesion

• hydrogen bonds result in water cohesion (surface tension)

• low surface tension of water

Tags

NGSS.MS-PS2-5

What word describes when water is attracted to other substances?

• cohesion
• adhesion
• capillary action
• surface tension

Water droplets take a spherical shape (as pictured) because of ____________

• adhesion
• cohesion
• capillary action
• solubility

A molecule with electrically charged areas is called a _______________.

• magnet
• polar molecule
• solution
• electrical molecule

Tags

NGSS.MS-PS1-1

Which end of the water molecule has a slightly positive charge?

• the oxygen end
• the hydrogen end
• both ends are slightly positive
• neither end is positive

Tags

NGSS.HS-PS1-3

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

Which of the following is LEAST likely to dissolve in water?

• nonpolar fats and oils
• polar sugar molecules
• salt made of a positive sodium ion and a negative chloride ion
• all of the substances will dissolve easily in water

Tags

NGSS.HS-PS1-3

Which characteristic of water will allow a paperclip to remain floating on water when the paperclip is gently placed on top of the water?

• adhesion

• surface tension due to cohesion

• solvent properties

• nonpolar

Which has a pH below 7?

• Acid
• Base