Answer:
69.3%
Explanation:
The question should read as follows:
A weak acid, HA, has a pKa of 4.357. If a solution of this acid has a pH of 4.005, what percentage of the acid is not ionized? Assume all H⁺ in the solution came from the ionization of HA.
The Henderson-Hasselbalch equation relates the pKa and pH of a solution to the ratio of ionized (A⁻) and unionized (HA) forms of a weak acid:
pH = pKa + log ([A⁻]/[HA])
Substituting and solving for [A⁻]/[HA]:
4.005 = 4.3574 = log([A⁻]/[HA])
-0.3524 = log([A⁻]/[HA])
[A⁻]/[HA] = 0.444/1
The percentage of acid that is not ionized (i.e. the percentage of acid in the HA form) is calculated:
[HA]/([A⁻] + [HA]) x 100% = 1/(1+0.444) x 100% = 69.3%
Answer:
By how many times would you expect Al2(SO4)3 to depress the F.P of water compared to sucrose C12H22011 ?.
Explanation:
The freezing point of a pure solvent decreases further by adding a nonvolatile solute.
This is called depression in freezing point.
When an ionic solute is dissolved then the depression in the freezing point is proportional to the number of ions present in the solution.
In aluminum sulfate, there are five ions formed as shown below:
But sucrose is a covalent compound and it does not undergo dissociation.
Hence, aluminum sulfate decreases the freezing point of water by five times compared to sucrose.
Explanation:
The answer is b) 12 i believe
The answer is 3.39 mol.
<span>Avogadro's number is the number of molecules in 1 mol of substance.
</span><span>6.02 × 10²³ molecules per 1 mol.
</span>2.04 × 10²⁴<span> molecules per x.
</span>6.02 × 10²³ molecules : 1 mol = 2.04 × 10²⁴ molecules : x
x = 2.04 × 10²⁴ molecules * 1 mol : 6.02 × 10²³ molecules
x = 2.04/ 6.02 × 10²⁴⁻²³ mol
x = 0.339 × 10 mol
<span>x = 3.39 mol
</span>
