I’m not sure but i think blue
Answer:
6.5x10⁻³M = [OH⁻]
Explanation:
The Kb of a Weak base as ethylamine is expressed as follows:
Kb = [OH⁻] [C₂H₅NH₃⁺] / [C₂H₅NH₂]
As the equilibrium of ethylenamine is:
C₂H₅NH₂(aq) + H₂O(l) ⇄ C₂H₅NH₃⁺(aq) + OH(aq)
The concentration of C₂H₅NH₃⁺(aq) + OH(aq) is the same because both ions comes from the same equilibrium. Thus, we can write:
Kb = [OH⁻] [C₂H₅NH₃⁺] / [C₂H₅NH₂]
6.4x10⁻⁴ = [X] [X] / [C₂H₅NH₂]
Also, we can assume the concentration of ethylamine doesn't decrease. Replacing:
6.4x10⁻⁴ = [X] [X] / [0.066M]
4.224x10⁻⁵ = X²
6.5x10⁻³M = X
<h3>6.5x10⁻³M = [OH⁻]</h3>
Answer:
<h2>18.87 cm³</h2>
Explanation:
The volume of a substance when given the density and mass can be found by using the formula
From the question we have
We have the final answer as
<h3>18.87 cm³</h3>
Hope this helps you
Nitric acid (HNO₃) is a strong acid. Hence, it completely dissociates into ions as H⁺ and NO₃⁻ in water.
The balanced equation is;
HNO₃(aq) →H⁺(aq) + NO₃⁻(aq)
The stoichiometric ration between HNO₃(aq) and H⁺(aq) is 1 : 1
Hence, the [H⁺] = <span>3.76 x 10</span>⁻²<span> M</span>
