What is electrical energy?

Calculate the percent ionization of a 0.15 M benzoic acid solution in pure water and in a solution containing 0.10 M sodium benz

Hoochie [10]

Answer:

% ionization for benzoic acid = 0.08%

% ionization for sodium benzoate = 2.5%

The percentage ionization differ significantly because benzoic acid is a weak acid while sodium benzoate is a salt of benzoic acid. Their extent of dissociation also differ because they were compared in different solutions

Explanation:

Ka for pure water = 1.0 * 10-⁷

Ka for sodium benzoate = 6.5*10-⁵

1. For benzoic acid (C6H5COOH)

C6H5COOH ==== C6H5COO‐ + H+

0.15M 0 0

0.15-x x x

Ka = [C6H5COO-] [H+] / [C6H5COOH]

Ka = [X] [X] / 0.15 - X

1.0*10-⁷ = [X]² / 0.15 - x

But x is negligible compared to 0.15,

(1.0*10-⁷)*0.15 = x²

Take square root of both sides,

X = 1.22 * 10-⁴

% ionization = ( [H+] / [C6H5COOH] ) * 100

% ionization = (1.22*10-⁷ / 0.15) * 100

% ionization = 0.08%

2. For C6H5COONa

Note: I will not repeat the same procedure of dissociation again since they're basically the same just the difference in ions

Ka for C6H5COONa = 6.5*10-⁵

6.5*10-⁵ = [X]² / (0.10 - X)

Cross-multiply both sides;

(6.5*10-⁵ * 0.10) = X²

Take square root of both side,

X= 2.5*10-³

% ionization = (2.5*10-³ / 0.10) *100

% ionization = 2.5%

5 0

3 years ago

Which of the following has no electrons? Use a periodic table. Question 1 options: H He H– He 2+ Save

Elodia [21]

An electron is a negatively charged subatomic particle present in the space outside the nucleus of an atom. The loss of electron from an atom results in the formation of cation whereas gaining of electron by an atom results in the formation of anion. The cation possesses positive charge due to loss of electron and anion possesses negative charge due to gain of electron.

The neutral atom has no charge on it.

For given atomic symbols:

$H$

The atomic number of hydrogen is 1 and the given symbol has no charge that means it is in its neutral state. So, the number of electrons in $H$ is 1.

$He$

The atomic number of helium is 2 and the given symbol has no charge that means it is in its neutral state. So, the number of electrons in $He$ is 2.

$H^{-}$

The atomic number of hydrogen is 1 and the given symbol has a negative charge that represents a gain of electron. So, the number of electrons in $H^{-}$ is 2.

$He^{2+}$

The atomic number of helium is 2 and the given symbol has two positive charge that represents loss of two electrons. So, the number of electrons in $He^{2+}$ is 0.

Hence, $He^{2+}$ has no electrons.

6 0

4 years ago

`Carbon Dioxide and Water are the _______ in a chemical reaction. 2. Reactants are also called the starting _______ in a chemica

natima [27]

The answer would be elector literally

8 0

3 years ago

Cu(NO3)2 + Zn (s) → Cu (s) + Zn(NO3)2 is an example of which type of reaction?

labwork [276]

Single replacements since cu is being replaced by zn

4 0