Reference no: EM1381855
The dominant bonds holding together non-polar compounds that are immersed in aqueous solution are _________, and the forces that hold pure solutions of non-polar compounds are ____________.
Select one:
a. hydrogen bonds;dispersion
b. hydrogen bonds;hydrophobic
c. hydrophobic;dispersion
d. hydrophobic;hydrogen bonds
The aqueous solution with the lowest pH is:
Select one:
a. 0.01 M HCl.
b. 0.1 M acetic acid (pKa = 4.86).
c. 0.1 M formic acid (pKa = 3.75).
d. 0.1 M HCl.
e. 10 to 12 M NaOH.
The Henderson-Hasselbalch equation expresses the pH of a solution as:
Select one:
a. The equilibrium constant of the acid and the dissociated form of the weak acid.
b. The weak acids pKa plus the log ratio of [dissociated form]/[acid]
c. The inverse of the pOH.
d. The weak acids pKa.
The greatest buffering capacity of weak acids is when-
Select one:
a. They are almost completely dissociated
b. They are almost completely undissociated
c. They are nearly half dissociated
d. The ratio between [A-] and [HA] is very high
e. None of the answers is correct
Which of the following is TRUE about the properties of aqueous solutions?
Select one:
a. A pH change from 5.0 to 6.0 reflects an increase in the hydroxide ion concentration ([OH-]) of 20 percent.
b. A pH change from 8.0 to 6.0 reflects a decrease in the proton concentration ([H+]) by a factor of 100.
c. Charged molecules are generally insoluble in water.
d. Hydrogen bonds form readily in aqueous solutions.
e. The pH can be calculated by adding 7 to the value of the pOH
Water is considered a universal solvent because-
Select one:
a. it can dissolve polar and non-polar compounds
b. it can dissolve both positively and negatively charged ions and polar compounds.
c. it can dissolve polar, non-polar, and charged compounds
d. none of the answers is correct
The fact that some pure solutions of hydrocarbons do not readily evaporate at room temperature is a result of-
Select one:
a. London dispersion forces.
b. The hydrophobic effect.
c. Extensive hydrogen bonding.
d. The existence of a permanent dipoles.
e. All of the answers are correct.
The bonding geometry of C,O,N is determined by-
Select one:
a. The number of electrons in their outer energy level
b. SP3 hybridization of orbitals in the valence shell
c. The number of double-or triple- bonds they make with other atoms in the molecule
d. All of the above