Answer:
The solution in beaker A is unsaturated
The solution in beaker B is saturated
Explanation:
A saturated solution is a solution that contains just as much solute as it can normally hold at a particular temperature. An unsaturated solution is a solution that contains less solute than it can normally hold at a particular temperature.
If more solute is added to a saturated solution, the added solute does not dissolve completely. However, if more solute is added to an unsaturated solution, the added solute dissolves.
Answer:
Modern whales evolved by natural selection over long time periods through descent from common ancestors
Explanation:
According to the evolutionary theory proposed by Darwin, natural selection is a biological process by which organisms adapt and change in response to their environment. In this case, ancient whales that were better suited to environmental conditions survived and produced more offspring than non-adapted individuals. In consequence, predominant adaptive traits observed in modern whales were favored by natural selection in the past, while unsuccessful phenotypes progressively disappeared.
Answer:
CH3CH2NH3+/CH3CH2NH2 would have the largest pKa
Explanation:
To answer this question we must know Kb of CH3CH2NH2 is 5.6x10⁻⁴, and for C6H5NH2 is 4.0x10⁻¹⁰. And the CH3CH2NH3+ and C6H5NH3+ are related with these substances because are their conjugate base. That means:
pKa of CH3CH2NH3+ = CH3CH2NH2; C6H5NH3+ = C6H5NH2
Also, Kw / Kb = Ka
Thus:
pKa of CH3CH2NH3+/CH3CH2NH2 is:
Kw / kb = Ka = 1.79x10⁻¹¹
-log Ka = pKa
pKa = 10.75
pKa of C6H5NH3+/ C6H5NH2 is:
Kw / kb = Ka = 2.5x10⁻⁵
-log Ka = pKa
pKa = 4.6
That means CH3CH2NH3+/CH3CH2NH2 would have the largest pKa