Answer:
The base must be ethylamine.
Explanation:
The pH of solution of a weak base gives us an idea about the Kb of the base.


![pOH=-log[OH^{-}]](https://tex.z-dn.net/?f=pOH%3D-log%5BOH%5E%7B-%7D%5D)
![[OH^{-}]=0.0062M](https://tex.z-dn.net/?f=%5BOH%5E%7B-%7D%5D%3D0.0062M)
The relation between Kb and hydroxide ion concentration is:
![Kb=\frac{[OH^{-}]^{2}}{[base]}](https://tex.z-dn.net/?f=Kb%3D%5Cfrac%7B%5BOH%5E%7B-%7D%5D%5E%7B2%7D%7D%7B%5Bbase%5D%7D)

Thus the weak base must be ethylamine.
Ionic compounds contain both cations and anions in a ratio that results in no net electrical charge
Answer: 32.94 g
Explanation: It's stoichiometry problem so balanced equation is required. The balanced equation is given below:

From the balanced equation, krypton and chlorine react in 1:2 mol ratio. We will calculate the moles of each reactant gas using ideal gas law equation(PV = nRT) and then using mol ratio the limiting reactant is figured out that helps to calculate the amount of the product formed.
for Krypton, P = 0.500 atm and for chlorine, P = 1.50 atm
V = 15.0 L
T = 350.8 + 273 = 623.8 K
For krypton, 
n = 0.146 moles
for chlorine, 
n = 0.439
From the mole ratio, 1 mol of krypton reacts with 2 moles of chlorine. So 0.146 moles of krypton will react with 2 x 0.146 = 0.292 moles of chlorine.
Since 0.439 moles of chlorine are available, it is present in excess and hence the limiting reactant is krypton.
So, the amount of product formed is calculated from moles of krypton.
Molar mass of krypton tetrachloride is 225.61 gram per mol.
There is 1:1 mol ratio between krypton and krypton tetrachloride.

= 32.94 g of 
So, 32.94 g of the product will form.
Answer:
1 mol compund has 6.023x10 to the power of 24
so 5.40 mol has (5.40 x 6.023 x 10 to the power of 23)
Explanation:
Explanation:
I did round the answer for it to match the sign fig, so you can unround it if you want to