Untitled Flashcard Set

What shape do water molecules have according to the lecture notes?

Water molecules are shaped like a wide V.

Why is water considered a polar molecule?

Because of the unequal sharing of electrons between hydrogen and oxygen.

What charge does oxygen have in a water molecule?

Oxygen has two regions of partial negative charge.

What are hydrogen bonds?

Attractions between partially positive hydrogen atoms of one water molecule and the partially negative oxygen of another.

What are the four properties of water mentioned in the notes?

Cohesive behavior, ability to moderate temperature, expansion upon freezing, and versatility as a solvent.

What is cohesion in the context of water?

Attraction between molecules of the same substance.

What influences the high specific heat of water?

Hydrogen bonding.

How does the temperature of water compare to other liquids when absorbing heat?

Water changes its temperature less than other liquids when it absorbs or loses heat.

What is heat of vaporization?

The quantity of heat a liquid must absorb for 1 g of it to be converted from liquid to gas.

Why does ice float in water?

Ice is less dense than liquid water.

What is the pH of pure water at 25 degrees Celsius?

7.

How do acids affect the hydrogen ion concentration of a solution?

Acids increase the hydrogen ion concentration.

What is a buffer?

A substance that minimizes changes in the concentrations of hydrogen and hydroxide in a solution.

What is the effect of ocean acidification on marine life?

It alters the delicate balance of conditions for life in the oceans.

What causes high humidity to increase discomfort on a hot day?

It inhibits the evaporation of sweat from the body.

Define hydrophilic substances.

Substances that have an affinity for water.

What is specific heat?

The amount of heat that can be absorbed or lost for 1 g of that substance to change its temperature by 1 degree Celsius.

What happens to the temperature of water when it evaporates?

The surface of the remaining liquid cools down.

What is the relationship between temperature and kinetic energy of molecules?

The faster the molecule moves, the greater its kinetic energy.

How does blood maintain pH stability despite the addition of strong acids?

Buffers help maintain relatively constant pH.

What is the relevance of water's high specific heat to coastal areas?

It moderates temperature fluctuations in coastal areas, stabilizing the climates.

What is the mole in chemistry?

A counting unit for atoms and molecules, equal to 6.02×10^23.

Why is water described as a versatile solvent?

Due to the polarity of the water molecule.