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
C. the expansion of the universe is accelerating
Answer:
624510100
Explanation:
Doing a conversion factor:
![0,0006245101[km]*\frac{1000[m]}{1 km} *\frac{1x10^{9} nanometer}{1 m} =624510100 [nanometer]](https://tex.z-dn.net/?f=0%2C0006245101%5Bkm%5D%2A%5Cfrac%7B1000%5Bm%5D%7D%7B1%20km%7D%20%2A%5Cfrac%7B1x10%5E%7B9%7D%20nanometer%7D%7B1%20m%7D%20%3D624510100%20%5Bnanometer%5D)
Answer:
option B
cementation and compaction