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>
Example :
If you use the subscript (aq) (=aquaris) , this means that the substance is in a solution.
Subscripts:
-aq-this means that the substance is in a solution
-s-this means that the substance is a solid(or precipitate)
-l-this means that the substance is a liquid
-g-this means that the subtance is a gas
Answer:
c) Fullerene and carbon nanotubes because they have empty spaces inside the molecules
Explanation:
Fullerene and carbon nanotubes would be the most desired in order to hold the cancer fighting drugs and to carry them through the body safely.
- These molecules have empty spaces in them.
- The cavities makes it possible for storage.
- As they pass through the body, they can be held perfectly well to their target site of action.
Oxidation is a process when an atom, a group of atoms, or an ion loses electrons.
For example,
Cu⁰ -------> Cu⁺² + 2e⁻. This is an oxidation process.
As we can see an oxidation number was 0, and it became +2. The oxidation number is increased. Oxidation number of the atom, when an atom has undergone oxidation, increases.
So, answer is b.False.
Answer: 1, 3, and 4
Explanation: i just did it
