Bellwork 1 Week 2 4th Nine Weeks

The molecular formula for water is

• W
• H2O
• 2HO
• H₂O

Which is NOT a property of water that helps or bodies function properly?

• Water is a natural antibiotic substance
• Water dissolves many substances
• Water cools when it evaporates
• Water can hold heat (maintain temperature)

Water dissolves ionic compounds, like NaCl, because water molecules...

• are non polar
• have a pH value of 14
• Have partially charged ends that interact with ions
• do not contain atoms

Which statement best describes an effect of the low density of frozen water on a lake?

• When water freezes it contracts, decreasing the water level in the lake.
• Water in a lake freezes from the bottom up
• Water removes thermal energy from the land, causing the lake to freeze
• When water in a lake freezes, it floats and provides insulation for the organisms below

A water molecule is polar. Its bent shape results in the following...

• slightly positive charge on hydrogen and slightly negative charge on oxygen
• slightly positive charge on hydrogen and slightly  positive charge on oxygen
• slightly negative charge on hydrogen and slightly positive charge on oxygen
• no change because its neutral

Water is cohesive, the molecules are attracted to one another because of hydrogen bonds. This attraction helps create...

• surface action
• surface tension
• ice
• solvents

Water helps maintain homeostasis in an organism, which of the following hold true to that?

• Its high specific heat
• Its ability to dissolve substances
• Its ability to be a polar molecules and have a pH of 7
• all of these

What property of water is being shown?

• polarity
• freezing point
• hydrogen bonds
• solution/universal solvent

What property of water is being shown?

• cohesion
• hydrogen bonds
• adhesion
• polarity

What is a universal solvent?

• temperature

• heat

• water

• acids