Chemistry of Life

Large bodies of water, such as lakes and oceans, do no quickly fluctuate in temperature. What is the reason behind this phenomenon? 

• Water is an acid

• Water has a high heat capacity

• Water is a universal solvent

• Water acts as a base

Tags

NGSS.HS-PS3-4

Water is essential for life. Its special properties make water the single most important molecule in plant life. Which of the following properties of water enables it to move from the roots to the leaves of plants?

• Water expands as it freezes

• Water is an excellent solvent

• Water exhibits cohesive behavior

• Water is able to moderate temperature

Tags

NGSS.MS-ESS2-4

Why does water move from the roots to the leaves of plants?

• Water is pushed by solutes

• Water is pulled by gravity

• Capillary action pulls the water molecules like a chain

• Water's cohesion causes it to "pull" towards the leaves

What property of water helps to moderate Earth’s temperature and even our constant internal body temperature?

• Cohesion

• Adhesion

• Density

• Specific heat capacity

Tags

NGSS.MS-ESS2-4

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

• Low surface tension of water

• Hydrogen bonds result in water cohesion (surface tension)

• Covalent bonds result in water cohesion

• Water striders have adapted to take advantage of water cohesion

Why does ice stay at the top of oceans instead of sinking to the bottom? 

• Ice is colder than liquid water

• Ice is less dense than liquid water

• Ice is more dense than liquid water

• Ice is warmer than liquid water

Water is often called the “universal solvent” because many substances can be dissolved in water. What property of water allows it to be such a universal solvent?

• Purity

• Polarity and cohesion

• High heat capacity

• Expansion upon freezing

Any compound that removes H+ ions to an aqueous solution and measures more than 7 on the pH scale:

• Base

• Solvent

• Acid

• Solute

Why does ice float?

• As water freezes, it expands and its density decreases.

• As water freezes, air becomes trapped between the hydrogen bonds of water molecules. 

• As water freezes, it takes up more hydrogen from the atmosphere, causing it to have greater buoyancy (floating ability). 

• As water freezes, it takes up more oxygen from the atmosphere, causing it to have greater buoyancy.

Substance in a solution that dissolves the other substance and is present in the greater amount:

• Solute

• Acid

• Solution

• Solvent