Biology Chapters 3, 4, 5, and 6

What is the Specific Heat capacity of water?

1 cal/ (gxC)

polar covalent bond

A covalent bond in which electrons are not shared equally

Surface Tension

A measure of how difficult it is to stretch or break the surface of a liquid

Four emergent properties of water that contribute to Earth's suitability for life

A) Cohesion fo Water Molecules B) Ability to moderate temperature C) Expansion upon Freezing D) Versatility as a Solvent

What Cohesion due to hydrogen bonding leads to:

A) Transport of Water B) Dissolved nutrients against gravity in plants

A kilocalorie is...

Amount of heat required to raise the temperature of 1 kilogram of water by 1 celsius

Adhesion

An attraction between molecules of different substances. Essentially the "clinging" of one substance to another

How does water have a high surface tension?

At the interface between water and air is an ordered arrangement of water molecules, hydrogen-bonded to one another and to the water below, but not to the air above. This asymmetry gives water an unusually high surface tension, making it behave as though it were coated with an invisible film

Explain why the central water molecule can hydrogen bond to four other molecules rather than three or five

Due to its polar covalent bonds, a water molecule has four regions of partial charge: two positive regions on the two hydrogens and two negative regions on the oxygen. Each of these can bind to a region of opposite partial charge on another water molecule

How do water molecules stay to pact together

Due to the hydrogen bonding

What is electronegativity, and how does it affect interactions between water molecules?

Electronegativity is the attraction of an atom for the electrons of a covalent bond. Because oxygen is more electronegative than hydrogen, the oxygen atom in H20 pulls electrons towards itself, resulting in a partial negative charge on the oxygen atom and partial positive charge on the hydrogen atom. Atoms in neighboring water molecules with opposite partial charges are attracted to each other, forming a hydrogen bond

The _____ a molecule moves, the ______ its kinetic energy

Faster; Greater

What is cohesion to a hydrogen bond

How the Hydrogen bond holds the molecule together

How are water molecules held together?

Hydrogen bonding due to opposite charged atoms

How does water moderate air temperature?

It does it by absorbing heat from air that is warmer and releasing the stored heat to air that is cooler. It also absorbs a large amount of heat

Why would a swimming pool contain more thermal energy than a pot of coffee

It has a much greater volume

What represents the average kinetic energy of the molecules in a body of matter?

Temperature

Why is it unlikely that two neighboring water molecules would be arranged like this? H H l / \ l O O l \ / l H H .

The Hydrogen atoms of one molecule, with their partial positive charges, would repel the hydrogen atoms of the adjacent molecule

A calories is...

The amount of heat it takes to raise the temperature of one gram of water by one celsius

How can something like raft spider walk on the surface of a pond?

The high surface tension of water enabled that, which in itself is formed from the collective strength of its hydrogen bonds

Explain the scientific process of burning your fingers on a pot on a stove

The specific heat of water is ten times greater than that of iron. The same amount of heat will raise the temperature of 1 g of iron much faster than one g of water

What is the strength of a hydrogen bond when water is in the liquid form?

Very fragile

The specific heat of a substance is...

defined as the amount of heat that must be absorbed or lost for 1 g of that substance to change its temperature by 1c

As water evaporates from a leaf...

hydrogen bonds cause water molecules leaving the veins to tug on molecules farther down and the upward pull is transmitted through the water-conducting cells all the way to the roots

Polar Molecule

molecule with an unequal distribution of charge, resulting in the molecule having a positive end and a negative end

Whenever two objects of different temperature are brought together, thermal energy...

passes from the warmer to the cooler object until the two are the same temperature

In water, the hydrogen is a lot less electronegative than the oxygen which causes which causes electrons of covalent bond to spend more time near oxygen. This is an example of a...

polar covalent bond

Thermal Energy is

the kinetic energy associated with the random movement of atoms or molecules

The charged regions in a water molecule are due to...

the polar covalent bonds

The thermal energy of a body of matter reflects...

the total kinetic energy

Structure of a water molecule

two hydrogen atoms and one oxygen atom that create a covalent bond

Because of the high specific heat of water relative to other materials...

water changes its temperature less than other liquids when it absorbs or loses a given amount of heat