Water-Napper

Question 1

General Statements on Water

Answer 1

• most abundant molecule in living systems, approx 70% mass of cell
• factor in structure of biomolecules
• water is participant in many biomchemical reactions

Question 2

Rule of Hydrogen Bonding

Answer 2

Anything that can form a hydrogen bond, MUST for a hydrogen bond.

Question 3

Hydrogen Bonds

Answer 3

• bonds are 1/25 the strength of covalent bonds
• linear hydrogen bonds are stronger than hydrogen bonds as part of an angle
• double the length of covalent bonds

Question 4

Water and Hydrogen Bonding

Answer 4

• Water can accept and donate two hydrogen bonds (because it is a dipole with oxygen being more electronegative)
• water hydrogen bonds with itself which leads to its high heat of vaporization(the amount of energy needed to vaporize a liquid) and high specific heat capacity (the amount of energy required to raise the temp one degree)

Question 5

Ice

Answer 5

Water as a solid(ice) is an arrangement where each water molecule forms exactly 4 bonds and therefore gives it a lower density than liquid water, making it float

Question 6

Water as a Solvent

Answer 6

water can and will dissolve polar compounds and compounds that can ionize. Water manipulates its charges to insulate what it is breaking down CL- attracts the hydrogen sides of water which facilitates its dissolving

Question 7

Hydrophilic

Answer 7

• Water loving molecules

- generally polar

Question 8

Hydrophobic

Answer 8

• water fearing

- generally nonpolar

Question 9

Solubility of Water

Answer 9

• more nonpolar groups, less soluble something is
• more polar groups means more soluble
• hydrogen bonding increases solubility

Question 10

pH Scale

Answer 10

• body pH is about 7.4

- a difference of one pH is a ten fold difference (ex 7 to 4 is 101010 or 1000 fold difference)

Question 11

Henderson-Hasselbach Equation

Answer 11

pH=pKa+log[A-]/[HA]

-in the equation the weak acid goes on the bottom, conjugate base on the top

Question 12

Buffers

Answer 12

• Solution that can resist changes in pH with the addition of acid or base
• Buffers are 1pH unit above, and below pKa values