Answer:
hello your question is incomplete attached below is the complete question
a) 0.12 M
b) Ka = 3.0 * 10^-7
c) Alizarin Yellow R
Explanation:
<u>A) Determine the concentration of the unknown acid</u>
The PH of the unknown acid before addition of NaOH is ; 3.72 ( weak acid )
First determine the moles of of NaOH
= molarity * volume
= 0.10 M * 30.0 ML = 0.0030 mol
at equivalence point
moles of NaOH = moles of unknown acid = 0.0030 mol
volume of unknown acid = 25.0 mL
Next calculate the concentration of the Acid ( HA )
= moles / volume
= 0.0030 mol / 25.0 mL
= 0.12 M
<u>b) Determine the Ka of the unknown acid </u>
attached below is the detailed solution
Ka = 3.0 * 10^-7
c) The indicator that would be a good choice to use in the titration of this acid with NaOH is ; Alizarin Yellow R . this is because the titration is between a strong base and a weak acid.
Answer:
619.465 kilometers
Explanation:
1609 m = 1 mile
so 385 miles is equal to 619465 meters (385 x 1609= 619465)
1000 meters = 1 km
so 619465 meters is 619.465 kilometers
Answer: -Ionic bonds form when one atom provides electrons to another atom. Covalent Bonds: Covalent bonds form when two atom shares their valence electrons. Metallic Bonds: Metallic bonds form when a variable number of atoms share a variable number of electrons in a metal lattice.
-Covalent Bonds.
Covalent Compounds. Contain no metals and no ions. Covalent compounds contain nonmetals only.
Example:
Ionic Compounds. A metal with a non-metal. Doesn't use prefixes for naming. Name the metal and change the nonmetal ending to -ide.
Explanation: Ionic bonds form when a nonmetal and a metal exchange electrons, while covalent bonds form when electrons are shared between two nonmetals. An ionic bond is a type of chemical bond formed through an electrostatic attraction between two oppositely charged ions.
The neutralization reaction is;
HClO₄(aq) + NaOH(aq) --> H₂O(l) + NaClO₄(aq)
Stoichiometry of HClO₄ to NaOH is 1:1
Therefore at equivalence an equal amount of NaOH reacts with an equal amount of HClO₄
The number of moles of NaOH in 1 L - 0.2 mol
Therefore in 21.52 ml of NaOH - 0.2/1000 x 21.52 = 0.004304 mol
the amount of HClO₄ moles that have reacted - 0.004304 mol
In 25 ml of HClO₄ - 0.004304 mol
Therefore in 1000 ml of HClO₄ - 0.004304/25 x 1000 = 0.172 mol
concentration of HClO₄ - 0.172 mol/L
