Answer:
D) 2.01 x 10⁻⁴ .
Explanation:
pH = 2.11
[ H⁺ ] =
Let the acid be HA
It will ionise as follows .
HA ⇄ H⁺ + A⁻
in equilibrium .30
Acid ionisation constant Ka = ![\frac{(10^{-2.11})^2}{0.3}](https://tex.z-dn.net/?f=%5Cfrac%7B%2810%5E%7B-2.11%7D%29%5E2%7D%7B0.3%7D)
= 2 x 10⁻⁴
Answer: The molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
Explanation:
Given:
= 43.6 mL,
= 0.125 M
= 25.0 mL,
= ?
Formula used to calculate the concentration of acid is as follows.
![M_{1}V_{1} = M_{2}V_{2}](https://tex.z-dn.net/?f=M_%7B1%7DV_%7B1%7D%20%3D%20M_%7B2%7DV_%7B2%7D)
Substitute the values into above formula.
![M_{1}V_{1} = M_{2}V_{2}\\0.125 M \times 43.6 mL = M_{2} \times 25.0 mL\\M_{2} = 0.218 M](https://tex.z-dn.net/?f=M_%7B1%7DV_%7B1%7D%20%3D%20M_%7B2%7DV_%7B2%7D%5C%5C0.125%20M%20%5Ctimes%2043.6%20mL%20%3D%20M_%7B2%7D%20%5Ctimes%2025.0%20mL%5C%5CM_%7B2%7D%20%3D%200.218%20M)
Thus, we can conclude that the molarity of an HCl solution is 0.218 M if 43.6 mL of a 0.125 M NaOH solution are needed to titrate a 25.0 mL sample of the acid.
Answer:
Drink Water, Eat food, Reproduce
Evolve etc.
Explanation: