The idea here is that you need to figure out how many moles of magnesium chloride,
MgCl
2
, you need to have in the target solution, then use this value to determine what volume of the stock solution would contain this many moles.
As you know, molarity is defined as the number of moles of solute, which in your case is magnesium chloride, divided by liters of solution.
c
=
n
V
So, how many moles of magnesium chloride must be present in the target solution?
c
=
n
V
⇒
n
=
c
⋅
V
n
=
0.158 M
⋅
250.0
⋅
10
−
3
L
=
0.0395 moles MgCl
2
Now determine what volume of the target solution would contain this many moles of magnesium chloride
c
=
n
V
⇒
V
=
n
c
V
=
0.0395
moles
3.15
moles
L
=
0.01254 L
Rounded to three sig figs and expressed in mililiters, the volume will be
V
=
12.5 mL
So, to prepare your target solution, use a
12.5-mL
sample of the stock solution and add enough water to make the volume of the total solution equal to
250.0 mL
.
This is equivalent to diluting the
12.5-mL
sample of the stock solution by a dilution factor of
20
.
Soap is the sodium or potassium salt of long chain of fatty acid. Fatty acids when treated with NaOH or KOH forms Soap. This process is called as Saponification. Examples of Soap are as follow,
1. Sodium Stearate C₁₇H₃₅COONa
2. Potassium Oleate C₁₇H₃₃COOK
Reaction of Soap with MgCl₂;
When Soap is treated with MgCl₂ or CaCl₂ it forms insoluble precipitate called S.C.U.M. The reactions with MgCl₂ are as follow,
2C₁₇H₃₅COONa + MgCl₂ --------> 2C₁₇H₃₅COOMg + 2 NaCl
2C₁₇H₃₃COOK + MgCl₂ --------> 2C₁₇H₃₅COOMg + 2 KCl
These reaction are often found in hard water. And this reaction decreases the effectiveness of soap.
<u>Answer:</u> The molality of non-electrolyte is 24.69 m
<u>Explanation:</u>
We are given:
Mole fraction of saturated aqueous solution = 0.310
This means that 0.310 moles of non-electrolyte is present.
Moles of water (solvent) = 1 - 0.310 = 0.690 moles
To calculate the mass from given number of moles, we use the equation:
Moles of water = 0.690 moles
Molar mass of water = 18 g/mol
Putting values in above equation, we get:
To calculate the molality of solution, we use the equation:
Where,
= Moles of solute (non-electrolyte) = 0.310 moles
= Mass of solvent (water) = 12.42 g
Putting values in above equation, we get:
Hence, the molality of non-electrolyte is 24.69 m
President George Washington’s leadership during the Whiskey Rebellion (1794) was important because it "(1) showed the ability of the new government to
<span>enforce federal law"</span>
Water is the BL base if it accepted a proton from NH4.
Can I get brainliest please?
