Midterms

• He stated that an acid is a substance that dissolves in water to produce H + ions, and a base is a substance that dissolves in water to produce OH − ions?

  Svante Arrhenius
• A substance that dissolves in water to produce H + ions?

  Arrhenius acid
• A substance that dissolves in water to produce OH − ions?

  Arrhenius base
• They stated that an acid is a species that loses a proton, and a base is a species that gains a proton?

  Johannes Brønsted and Thomas Lowry
• A substance that donates a hydrogen ion (H+)?

  Brønsted–Lowry acid
• A substance that accepts a hydrogen ion?

  Brønsted–Lowry base
• When a base accepts a proton, the base is converted to its ?

  conjugate acid
• When an acid transfers a proton to a base, the acid is converted to its?

  conjugate base
• An acid can be positively charged, neutral, or negatively charged? ( True or False)

  True
• A base can be negatively charged or neutral? ( T or F)

  True
• Acids are classified as monoprotic, diprotic, or triprotic, depending on the number of protons

  each may give up? (T or F)

  True
• Several molecules and ions appear in both the acid and conjugate base columns; that is, each can function as either an acid or a base? ( True or False)

  True
• There is a direct relationship between the strength of an acid and the strength of its conjugate

  base?

  False ( inverse)
• it is the one that ionizes completely in aqueous solution?

  strong acid or strong base
• it is the one that only partially ionizes in aqueous solution?

  weak acid or weak base
• The degree to which an acid (HA) dissociates in an aqueous solution is indicated by the equilibrium constant of the reaction?

  Keq
• The degree to which an acid (HA) dissociates is normally determined in a dilute solution, so the concentration of water remains essentially constant?

  Ka
• Combining the two constants (Keq and

  H2O) allows the equilibrium expression to be rewritten using a new equilibrium constant?

  acid dissociation constant
• The larger the acid dissociation constant, the stronger the acid—that is, the greater its tendency to lose a proton?

  pKa
• The strength of an acid is generally indicated by its ?

  pKa
• The concentration of protons in a solution is indicated by ?

  pH
• characterized by the presence of a positively polarized hydrogen atom ?

  Organic acids
• they occur abundantly in all living organisms and involved in almost all metabolic pathways. this are most common organic acids?

  Carboxylic Acids (COOH)
• pKa values ranging from about?

  3 to 5 - weak acids
• characterized by the presence of an atom with a lone pair of electrons that can bond to H+ ?

  Organic Bases
• containing compounds such as a methylamine are the most common organic bases?

  Nitrogen
• containing compounds can also act as bases when reacting with a sufficiently strong acid?

  Oxygen
• compounds that result from replacing one or more of the hydrogens bonded to ammonia with a carbon-containing substituent?

  Amines (NH2)
• most common organic bases - high pKa values?

  Amines (NH2)
• building blocks from which the proteins present in all living organisms are made?

  Amino acids
• amino acids exist primarily in a doubly charged form called a?

  Zwitterion
• arises because amino acids have both acidic and basic sites within the same molecule and therefore undergo an internal acid–base reaction?

  Zwitterion
• He stated that Acid is a species that can form a new covalent bond by accepting a pair of electrons; a base is a species that can form a new covalent bond by donating a pair of electrons?

  Gilbert Lewis
• Substance that accepts an electron pair?

  Lewis acid
• Substance that donates an electron pair?

  Lewis base
• the weaker conjugate base gives?

  Stronger acid
• the stronger conjugate base gives?

  weaker acids
• it is determined by the stability of the conjugate base that forms when the acid loses its proton: the more stable the conjugate base, the stronger the acid.

  strength of an acid
• it is affected by electronegativity, resonance,

  hybridization, induction, and size?

  stability
• it is the occurrence of 2 different structures

  for the same formula?

  Resonance Effect