citric acid has an acid dissociation constant of 8.4 x 10^-4 it would be most effective for preparation of a buffer with a pH of
1 answer:
Answer:
(B) 3
Explanation:
Citric acid has an acid dissociation constant (Ka) of 8.4 × 10⁻⁴. When it forms a buffer with its conjugate base (citrate), we can calculate the pH using the Henderson-Hasselbalch's equation.
The optimum range of pH is pKa ± 1. The pKa is -log Ka = -log (8.4 × 10⁻⁴) = 3.1. The buffer would be more effective for pH between 2.1 and 4.1, especially around 3.1. So the best choice is (B) 3.
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Answer: The concentration of is 0.234 M
Explanation:
According to the neutralization law,
where,
= basicity
= 2
= molarity of
solution = ?
= volume of
solution = 50.0 ml
= acidity of
= 1
= molarity of
solution = 0.375 M
= volume of
solution = 62.5 ml
Putting in the values we get:
Therefore concentration of is 0.234 M
Percentage recovery gives us an idea of the amount of pure substance recovered after the chemical reaction. Percentage recovery can be more than 100 % or less than 100 %. Usually, in any experiment performed the weight percentage recovery will be less than 100. Percent recovery values greater than 100 show that the recovered compound is contaminated.
Amount of acetaminophen initially taken = 350 mg
Amount of acetaminophen obtained after recovery =185 mg
=
= 52.9%
Answer:
a. Clay
b. Sandy Loam
c. Sandy Clay
d. Loamy Sand
Explanation:
Based on the soil texture triangle, the soil texture for the following combination of sand, silt and clay are;
a. Sand 20 percent; Silt 20 percent;Clay 60 percent: ____ CLAY
b. Sand 60percent; Silt 30percent; Clay 10percent: ___ SANDY LOAM
c. Sand 50percent; Silt 10percent;Clay 40 percent: ____ SANDY CLAY
d. Sand 80 percent; Silt 15 percent; Clay 5percent:_____ LOAMY SAND
