The answer is b) 12 i believe
Answer:
Hi
True
Explanation:
Since on the inner and outer surfaces of the membrane, a series of negatively charged amino acids are found, which increase the local concentration of cations. The path of the ions begins on the inner surface filled with water molecules where the ion can retain its hydration sphere. Two thirds of its interior in the membrane the inside of the channel narrows in the region of the selectivity filter, forcing the ion to separate from the water molecules. Oxygen atoms in the selectivity filter replace the water molecules in the K+ hydration sphere, forming a series of coordination spheres through which the ion moves. The preferential stabilization of K+ against Na+ is the basis of the ion selectivity of this filter.
Answer:
Concentration: 0.185M HX
Ka = 9.836x10⁻⁶
pKa = 5.01
Explanation:
A weak acid, HX, reacts with NaOH as follows:
HX + NaOH → NaX + H2O
<em>Where 1 mole of HX reacts with 1 mole of NaOH</em>
To solve this question we need to find the moles of NaOH at equivalence point (Were moles HX = Moles NaOH).
18.50mL = 0.01850L * (0.20mol / L) = 0.00370 moles NaOH = Moles HX
In 20.0mL = 0.0200L =
0.00370 moles HX / 0.0200L = 0.185M HX
The equilibrium of HX is:
HX(aq) ⇄ H⁺(aq) + X⁻(aq)
And Ka is defined as:
Ka = [H⁺] [X⁻] / [HX]
<em>Where [H⁺] = [X⁻] because comes from the same equilibrium</em>
As pH = 2.87, [H+] = 10^-pH = 1.349x10⁻³M
Replacing:
Ka = [H⁺] [H⁺] / [HX]
Ka = [1.349x10⁻³M]² / [0.185M]
Ka = 9.836x10⁻⁶
pKa = -log Ka
<h3>pKa = 5.01</h3>
Protons and neutrons, just like in the nucleus of every other element.
I believe it is <span>d. the bonds of both the reactants and the products are formed.</span>
