<u>Question:</u>
For the cell constructed from the hydrogen electrode and metal-insoluble salt electrode, B) calculate the mean activity coefficient for 0.124 b HCl solution if E=0.342 V at 298 K
<u>Answer:</u>
The mean activity coefficient for HCl solution is 0.78.
<u>Explanation:</u>
Activity coefficient is defined as the ratio of any chemical activity of any substance with its molar concentration. So in an electrochemical cell, we can write activity coefficient as γ. The equation for determining the mean activity coefficient is

As we know that
= 0.22 V and E = 0.342 V, the equation will become








So, the mean activity coefficient is 0.78.
Chemical property. Chemical property refers to the characteristic changed
Answer:
C). The Bohr-Rutherford model
Explanation:
The 'Bohr-Rutherford model' of the atom failed to elaborate on the attraction between some substances. It essentially targeted hydrogen atoms and failed to explain its stability across multi-electrons. The nature and processes of the chemical reactions remained unillustrated and thus, this is the key drawback of this model. Thus, <u>option C</u> is the correct answer.
Answer: The mass density is 1166.36
.
Explanation:
Given: Weight of sample in air
= 500 N
Weight of sample in alcohol
= 200 N
Specific gravity = 0.7 = 
Formula used to calculate Buoyant force is as follows.

Hence, volume of the material is calculated as follows.

where,
= Buoyant force
= specific gravity
g = acceleration due to gravity = 9.81
Substitute the values into above formula.

Now, mass of the material is calculated as follows.

Therefore, density of the material or mass density is as follows.

Thus, we can conclude that the mass density is 1166.36
.
That there are empty space in the atom
That almost all of the mass is concentrated at the center of the atom