Answer: Option (b) is the correct answer.
Explanation:
A spontaneous reaction is defined as the process which tends to occur on its own. It does not require any external factor or force in order to start itself.
For example, when we dissolve KCl in water then potassium chloride being ionic in nature will dissolve on its own. Hence, it will be a spontaneous process.
And, a non-spontaneous reaction is defined as a process for the completion of which we have to provide certain conditions.
Thus, we can conclude that the statement it does not require any external action to begin, is true about a spontaneous process.
<em>A cylinder of argon gas contains 50.0 L of Ar at 18.4 atm and 127 °C. How many moles of argon are in the cylinder?</em>
<em />
Number moles of Argon : 28.03
<h3>Further explanation</h3>
Given
The volume of gas=50 L
P = 18.4 atm
T = 127+273=400 K
Required
moles of Argon
Solution
Use ideal gas Law :

Coefficients is the answer
2 HBr + Mg(OH) 2 yields Mg(Br) 2 + 2 H2O
M1V1 = M2V2
(0.245 M)(37.5 mL) = (M2)(18.0 mL)
9.1875 = (M2)(18.0 mL)
9.1875/(18.0 mL) = (M2)(18.0 mL)/(18.0 mL)
0.51041
this is not the complete answer as the mol to mol ratio must be considered!
For every 2 mols of HBr there is 1 mole of <span>Mg(OH)2; ratio = 2:1
</span>0.51041 / 2 = 0.25520
M2 = 0.25520
0.25520 M of<span> Mg(OH)2 solution</span>