c3 bio

The concentration of the appetite-regulating hormone ghrelin is about 1.3 x 10^-10 M in the blood of a fasting person. How many molecules of ghrelin are in 1L of blood?

A liter would contain 7.8 x 10^13 molecules of ghrelin (1.3 x 10^-10 moles per liter x 6.02 x 10^23 molecules per mole)

1.3x10^-10 x Avogadros number

What is the main reason that the oceans are becoming more acidic?

Absorption by the oceans of carbon dioxide generated by burning fossil fuels.

How much carbon dioxide from the atmosphere is absorbed by the oceans a daily basis?

20 million metric tons

What is the chemical reaction responsible for the oceans becoming more acidic?

Carbon dioxide reacts with seawater, forming carbonic acid.

How are oyster larvae affected by the ocean acidification?

Oyster larvae cannot grow shells in acidified oceans waters.

Which of the following are consequences of ocean acidification? Select all that apply

Claims, mussels, lobsters, and shrimp are not able to form strong enough shells.

Because of ocean acidification, the price of which of the following foods is most likely to increase?

Shellfish

Each water molecule is joined to ______ other water molecules by _____ bonds.

Four; hydrogenp

The unequal sharing of electrons within a water molecule makes the water molecule _____.

Polar

The tendency of an atom to pull electrons toward itself is referred to as its ____.

Electronegativity

In this molecule H2O, what type of bond is found between the oxygen and hydrogens?

Polar covalent

Which statement must be mentioned in explaining why amphipathic molecules line up at a water surface?

Polar groups attract one another.

Dissolving is best described as ...

A mingling of molecules and/or ions.

Water is a source of _______ for chemical reactions in cells.

Hydrogen and oxygen atoms

Which statement is true of water's tensile strength?

It results from hydrogen bonding

It helps to pull water through the plants

It involves both cohesion and adhesion

Water has surface tension because ....

Hydrogen bonds between surface water molecules resist being stretched.

Which of the following helps most to explain why water has a high specific heat?

A water molecule can make 4 hydrogen bonds

Which factor is important in making it possible to cool yourself by sweating?

Molecules collide with varied angles and speeds.

Hydrogen bonds are relatively week.

Though you add heat, the temperature of boiling water remains constant because....

It takes energy to break hydrogen bonds

Which statement helps to explain why ice is less dense than liquid water?

Water molecules make hydrogen bonds at define angles

Cold molecules move less than warm molecules.

The open spaces in water's crystals structure makes it possible for ....

Aquatic life to exist in North Pole.

Why doesn't oil mix with water?

Polar molecules attract one another.

A compound that donates hydrogen ions to a solution is_____.

An acidic

The specific heat of a substance is ______.

The amount of heat that must be absorbed or lost for 1 g of that substance to change its temperature by 1C

An acid is ______.

A compound that donates hydrogen ions to a solution

The partial charges on water molecule occurs because of _____.

The unequal sharing of electrons between the hydrogen and the oxygen atoms of a water molecule.

A mole of methanol (CH3OH) weights 32 g. The number of grams of methanol that are needed to produce 1 L of a millimolar solution is ______.

0.032

______ is an emergent property of water that allows insects like the raft spider to walk on water.

Surface tension

When the pH of a solution shifts from 3 to 7, the hydrogen concentration has changed, and ________.

Has decreased by 10,000 times

Water moves up a plant because of hydrogen bonds by a process called ___.

Cohesion and adhesion

The phenomenon responsible for maintaining the upward movement of water through a vessel is _____.

Cohesion

Water is a polar molecule. This means that ______.

The opposite ends of the molecule have opposite electrical charges.

Adding a base tends to _______ of a solution.

Lower the hydrogen ion concentration and increase the pH

Sweeting has a cooling effect because water's high _____.

Heat of vaporization

A substance that reduces the hydrogen ion concentration is _____.

A base

Urine, at a pH 6, contains _______ H+ as household bleach, at pH 13.

10,000,000 times as much

A solution at pH 10 contains ______ than the same amount of solution at pH 8.

100 times less H+

No polar molecules that cluster away from molecules are called ______ molecules.

Hydrophobic

Adhesion is best described as _______.

The clinging of one substance to another substance

Buffers are _____.

Substances that minimize the changes in concentration oh H+ and OH- in a solution.

Glucose has a molecular mass of 180 daltons. To make a 2-molar (2 M) solution of glucose ____.

Stir 360 g of glucose in water to dissolve the sugar, and then add enough water to bring the total volume of the solution up to 1L

You can fill a glass of water to just slightly above the rim without it spilling over the glass. What property of water best explains this phenomenon?

Surface tension

Many mammals control their body temperature by sweating. Which property of water is most directly responsible for the ability of sweat to lower body temperature?

Absorption of heat by breaking of hydrogen bonds.

When ice forms, the _____ are farther apart than liquid water, allowing the ice to form and organized crystals structure and float.

Hydrogen bonds

The absorption of human-generated CO2 by the oceans ____.

Reduces the carbonate ion concentration in the oceans and threatens calcifying organisms in marine ecosystems.

Increases the oceans acidity and lowers pH.

Increases the hydrogen ion concentration in the oceans but decreases the carbonate ion concentration and threatens the liability of the oceans for calcifying organisms.

Hydrophilic molecules ____.

Are charged molecules that a attracted to the partial charge of the water molecule.

All of the following are hydrogen bonding except ______.

No polar covalent bonding

The ability of water molecules to form hydrogen bonds with other water molecules and water's ability to dissolve substances that have great charges or partial charges are _____.

Both caused by water's partial charges

Hydrophobic

Uncharged, nonionic substances that seem to repeal water.

The amount of heat requiered to convert 1 g of any substance from the liquid to the gaseous state is defined as _______.

The heat of vaporization of that substance