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:
Explanation:
density is mass over volume
Mass = 163 grams
Volume = 58.5 - 50.0 = 8.5
density = 163 / 8.5
density = 19.176
To 3 figures that 19.2 grams / mL
Answer:
2 hydrogen and 1 oxygen
Explanation:
H2O
Hydrogen has the coefficient so you multiply 1 by 2 and it equals 2
Oxygen does not have any sub or coe so its automatically 1
Answer: -
C. Electrons
Explanation: -
Most of the space in an atom is empty. Through this space the electrons revolve around the centrally placed nucleus.
Inside the nucleus are present the protons and the neutrons. The nucleus size is very small compared to the rest of the atom.
Electrons carry negative charge, protons are positive and neutrons are neutral.
The answer is 15g
The mass of a substance when given the density and volume can be found by using the formula
Mass = Density x Volume
From the question
Density of chloroform=1.5 g/ml
Volume=10mL
We have
Mass=1.5x10
We have the final answer as
15g
