A buffer solution contains an equivalent amount of acid and base. The pH of the solution with an acid dissociation constant (pKa) value of 3.75 is 3.82.
<h3>What is pH?</h3>
The amount of hydrogen or the proton ion in the solution is expressed by the pH. It is given by the sum of pKa and the log of the concentration of acid and bases.
Given,
Concentration of salt [HCOO⁻] = 0.24 M
Concentration of acid [HCOOH] = 0.20 M
The acid dissociation constant (pKa) = 3.75
pH is calculated from the Hendersons equation as,
pH = pKa + log [salt] ÷ [acid]
pH = 3.75 + log [0.24] ÷ [0.20]
= 3.75 + log (1.2)
= 3.75 + 0.079
= 3.82
Therefore, 3.82 is the pH of the buffer.
Learn more about pH here:
brainly.com/question/27181245
#SPJ4
When the balanced reaction equation is:
2HCl(aq) + Ca(OH)2(aq) → CaCl2(aq) + 2H2O(l)
from the balanced equation, we can get the molar ratio between HCl & Ca(OH)2
2:1
∴ the volume of Ca(OH)2 = 15.8 L HCl * 1.51 m HCl * (1mol Ca(OH)2/ 2mol HCl) * (1L ca(OH)2/0.585 mol Ca(OH)2
= 20.4 L
Astronauts experience weightlessness which is the apparent loss of weight of an object that is falling in gravitational field
Answer: The correct option is 3.
Explanation: We are given a compound which is made up of iron and oxygen only. The ratio of the two are given as:

This means that, number of iron ions are 2
Number of oxide ions are 3
From the above information, the formula becomes : 
The valency of iron = 3
Valency of oxide = 2
This compound is named as iron (III) oxide.
Hence, the correct option is 3