
<u>Difference </u><u>between </u><u>Atomic </u><u>mass</u><u>, </u><u>relative </u><u>atomic </u><u>mass </u><u>and </u><u>average </u><u>atomic </u><u>mass</u><u> </u><u>:</u><u>-</u>
<h3><u>Atomic </u><u>Mass </u><u>:</u><u>-</u></h3>
- Atomic mass is the mass of neutrons and protons present in the nucleus of an atom .
- It is always calculated for a single element and having direct value
- For isotopes also, the atomic mass is calculated separately . Example :- <u>Carbon </u><u>1</u><u>2</u><u> </u><u>,</u><u> </u><u>carbon </u><u>1</u><u>3</u><u> </u><u>and </u><u>carbon </u><u>1</u><u>4</u><u> </u><u>have </u><u>different </u><u>atomic </u><u>mass</u><u>. </u>
- The SI unit of Atomic mass is " u" and "amu"
<h3>
<u>Relative </u><u>Atomic </u><u>mass </u><u>:</u><u>-</u></h3>
- Relative atomic mass is mean mass of the atoms of an element which is compared to the 1/12th mass of carbon - 12 .
- Carbon - 12 is taken as a relative when we calculate the relative atomic mass of any element
- For calculating relative atomic mass, we need to know the masses, percentage and abundance of all types of elements
- Relative atomic mass is a dimension less quantity
<h3><u>Average </u><u>Atomic </u><u>Mass </u><u>:</u><u>-</u></h3>
- Average atomic mass is the average mass of an atoms of a particular element by considering it's isotopes
- While we calculate average atomic mass is a standardized number. Whereas, Average atomic mass sometimes varies geologically .
- It also includes percentage, abundance and masses of given element .
- In average atomic mass, We do not compare mean value with the 1/12 mass of carbon - 12
- The unit of Average atomic mass is "Amu" or " u " .
Answer:
The reactions free energy 
Explanation:
From the question we are told that
The pressure of (NO) is 
The pressure of (Cl) gas is 
The pressure of nitrosly chloride (NOCl) is 
The reaction is
⇆ 
From the reaction we can mathematically evaluate the
(Standard state free energy ) as

The Standard state free energy for NO is constant with a value

The Standard state free energy for
is constant with a value

The Standard state free energy for
is constant with a value

Now substituting this into the equation

The pressure constant is evaluated as

Substituting values


The free energy for this reaction is evaluated as

Where R is gas constant with a value of 
T is temperature in K with a given value of 
Substituting value
![\Delta G = -43 *10^{3} + 8.314 *298 * ln [0.0765]](https://tex.z-dn.net/?f=%5CDelta%20%20G%20%20%3D%20-43%20%2A10%5E%7B3%7D%20%2B%208.314%20%2A298%20%2A%20ln%20%5B0.0765%5D)


Answer: The number of protons
Explanation: