Chapter 2: Aqueous Chemistry

Question 1

H2O ; central oxygen forms what type of bond?

Answer 1

Oxygen forms covalent bonds with two hydrogen atoms. It leaves an unpaired pair of electrons.

Question 2

Is water molecule polar or non-polar

Answer 2

Because water is in a tetrahedral arrangement it is POLAR

Question 3

Hydrogen Bond

Answer 3

A weak electrostatic attraction between oppositely charged particles that have some covalent characters.

Question 4

How many hydrogen bonds can a water molecule have.

Answer 4

Water can potentially participate in four hydrogen bonds. Because it has two hydrogen atoms to donate to a hydrogen bond and the two pairs of unshared electrons.

Question 5

Ionic Interactions

Answer 5

Intermediate in strength to covalent bonds and hydrogen bonds

Question 6

Van der waals interactions

Answer 6

weaker than hydrogen bonds. It is an interaction between two strongly polar groups is known as dipole-dipole.

Question 7

Weak vander waals interactions ar also known as

Answer 7

London dispersion forces that occur between nonpolar molecules.

Question 8

Dielectric Constant

Answer 8

measure of solvent’s ability to diminish the electrostatic attractions between dissolved ions. The higher the constant of the solvent the less the ions associate with each other

Question 9

Polar water molecules surround water by aligning what?

Answer 9

They align their partial charges with the oppositely charged ions.

Question 10

Solute

Answer 10

A dissolved particle

Question 11

Why can water dissolve polar compunds

Answer 11

This is because multiple h bonds can be formed.

Question 12

Glucose and other readily hydrated substances are said to be what?

Answer 12

Hydrophilic (water loving)

Question 13

Compounds that lack polar groups are said to be what in wate

Answer 13

hydrophobic and insoluble

Question 14

Polar substance is added to water

Answer 14

There is a loss in entropy because the highly mobile water has lost some of its freedom to rapidly form, break and re-form hydrogen bonds with other molecules.

Question 15

The exclusion of nonpolar substances from an aqueous solution is known as the?

Answer 15

Hydrophobic effect

Question 16

Adding more nonpolar molecules do what

Answer 16

They aggregate and the entropy of the system increases.

Question 17

Most lipids are what type of -philic

Answer 17

Most lipids are amphiphilic or amphipatic. They experience both hydrophilic interactions and the hydrophobic effect.

Question 18

Micelle

Answer 18

A sphere that has a hydrophobic core.

Question 19

Bilayers

Answer 19

Amphiphilic lipids that provide a structural basis for biological membranes will from a two-layered sheet known as the lipid bilayer.

Question 20

Lipid vesible

Answer 20

It forms to eliminate the solvent exposed edges.

Question 21

Bilayer prevents diffusion of polar substances

Answer 21

Solutes that are within the vesicle will not be able to easily leave because of the lipid bilayer

Question 22

Ionization of water formula

Answer 22

Question 23

Ionization constant of water.

Answer 23

K_W=K[H₂O]=[H⁺][OH^-], K_w=10^-14

Question 24

pH log formula

Answer 24

pH=-log[H⁺]

Question 25

The Henderson-Hasselbalch Equation

Answer 25

The equation relates to the pH of a solution to the pK of an acid and the concentration of the HA and A^-.

Question 26

Buffer

Answer 26

Prevents dramatic changes in pH that would otherwise occur.

Question 27

How buffers resist changes in pH

Answer 27

HCL→ H⁺+Cl^- large increase in [H⁺]

HCL + A^-→ HA +Cl^- Small increase in [H⁺]

The same can be applied to the strong base of NaOH. Buffer solutions resist pH changes because in this case some of the added protons combine with the conjugated base to reform the acid; no longer forms H. For NaOH the added hydroxide ions form more water and don’t contribute to the decrease of H.

Question 28

Titration Curve

Answer 28

Before the acid or base is added. The midpoint is where the solution hits equilibrium (pH=pK). Afterwards the pH will change to either basic or acidic depending on the solution.

Question 29

The bicarbonate buffer system

Answer 29

Elimination or retention of CO₂ can shift the equilibrium in order to promote or prevent the loss of H⁺ from the body.

Question 30

Bicarbonate reabsorption H⁺

Answer 30

Question 31

Bicarbonate Production

Answer 31