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pH decreases as the hydrogen ion concentration increases.
<u>Explanation:</u>
When there is a decrease in pH, that is pH decreases from 6 to 3 then the acidity increases.
That is the pH is between 1 to 7 then it is acidic
When the pH is 7 then it is neutral
When the pH is between 7 to 14 then it is basic
As the H⁺ ion concentration increases, then the pH value decreases, here pH decreases from 6 to 3.
So the concentration of Hydrogen ion increases, pH decreases.
Alkali metals have the lowest electronegativities, while halogens have the highest.
In order of increasing percent water content:CoCl₂.6H₂O, Ba(OH)₂.8H₂O, MgSO₄.7H₂O
<h3>Further explanation</h3>

CoCl₂.6H₂O.MW=237.90 g/mol
6H₂O MW = 6.18=108 g/mol

MgSO₄.7H₂O.MW=246.48 g/mol
MW 7H₂O = 7.18=126 g/mol

Ba(OH)₂.8H₂O MW=315.48 g/mol
MW 8H₂O = 8.18=144 g/mol

The mole fraction of KCl in the solution is 0.1051
calculation
mole fraction of KCl in solution = moles of KCl / total number of moles(moles of KCl +moles of H2O)
moles=mass/molar mass
mass of KCl=32.7g
molar mass of KCl= 39 +35.5
moles of KCl is therefore= 32.7g/74.5 g/mol=0.439 moles
find the moles of H2O= mass of H2O/molar mass
mass of H2O=100-32.7=67.3g
molar mass of H2O=( 1 x2) +16=18 g/mol
moles = 67.3/18 =3.739 moles
total moles=3.739+0.439=4.178 moles
mole fraction is therefore=0.439/4.178=0.1051