Answer:
The value of entropy change for the process 
Explanation:
Mass of the ideal gas = 0.0027 kilo mol
Initial volume
= 4 L
Final volume
= 6 L
Gas constant for this ideal gas ( R ) = 
Where
= Universal gas constant = 8.314 
⇒ Gas constant R = 8.314 × 0.0027 = 0.0224 
Entropy change at constant temperature is given by,

Put all the values in above formula we get,
![dS = 0.0224 log _{e} [\frac{6}{4}]](https://tex.z-dn.net/?f=dS%20%3D%200.0224%20%20log%20_%7Be%7D%20%5B%5Cfrac%7B6%7D%7B4%7D%5D)
This is the value of entropy change for the process.
B. electrons have a negative electrical charge
The mass change, or the mass defect, can be calculated by the formula that is very known to be associated with Albert Einstein.
E = Δmc²
where
E is the energy gained or released during the reaction
c is the speed of light equal to 3×10⁸ m/s
Δm is the mass change
(1.715×10³ kJ)(1,000 J/1 kJ) = Δm(3×10⁸ m/s)²
Δm = 1.91×10⁻¹¹ kg
HCl is a strong acid therefore complete ionisation takes place
HCl ---> H⁺ + Cl⁻
1 mol of HCl dissociates to form 1 mol of H⁺
NaOH is a strong base therefore complete ionisation takes place
NaOH ---> Na⁺ + OH⁻
1 mol of NaOH dissociates to form 1 mol of OH⁻ ions
equal number of moles of HCl and NaOH will dissociate to give out an equal number of moles of H⁺ and OH⁻ ions.
H⁺ + OH⁻ --> H₂O
equal amount of H⁺ and OH⁻ together forms H₂O
since all the H⁺ and OH⁻ have now reacted to form water molecules the solution now becomes neutral as there are no excess H⁺ ions to make the solution acidic and no excess OH⁻ ions to make the solution basic.
Therefore the solution will be neutral.