At the boiling point, the vapor pressure of a liquid is equal to the atmospheric pressure.
Answer: Option (B) is the correct answer.
Explanation:
Expression for the given decomposition reaction is as follows.

Let us assume that x concentration of
is present at the initial stage. Therefore, according to the ICE table,

Initial : x 0
Change : - 0.1 
Equilibrium : (x - 0.1) 0.2
Now, expression for
of this reaction is as follows.

Putting the given values into the above formula as follows.



x = 0.12
This means that
= x = 0.12 atm.
Thus, we can conclude that the initial pressure in the container prior to decomposition is 0.12 atm.
Table Giving Answer
Element Atomic mass % Amount
Mg_24 24 79 18.96
Mg_25 25 10 2.5
Mg_26 26 11 2.86
Total 24.32
Discussion
The method of calculation for this table, which was done in Excel (a spread sheet) is shown below. Assume that there is 100 grams of material of "pure" magnesium. What is it's mass?
<em><u>Sample Calculation</u></em>
The the sample atomic mass = 24
Mass = % * sample atomic mass
Mass = 79% * 24
Mass = (79/100) * 24
Mass = 18.96
<em><u>Note</u></em>
The other two elements are found exactly the same as the sample calculation.
Then all you do is add the 3 masses together.
Answer
The mass of Mg to 1 decimal place is 24.3 <<<< Answer.
"A <span>gas condensing to a liquid" is the one system among the following choices given in the question where the entropy is decreasing. The correct option among all the options that are given in the question is the fourth option or option "D". I hope that this is the answer that has come to your desired help.</span>
Answer:
Na the valency electrons is 1
The ion charge is positive 1
K the valency electrons is 1
The ion charge is positive 1
Explanation:
Mg the valency electron is 2 The ion charge is positive 2
Ca the valency electron is 2 The ion charge is positive 2
Al the valency electron is 3 The ion charge is positive 3
O the valency electron is 2 The ion charge
is negative 2
F the valency electron is 1 The ion charge is negative 1
Cl the valency electron is 1 The ion charge
is negative 1
N the valency electron is 3 The ion charge is negative 3
S the valency electron is 2 The ion charge is
negative 2