Answer:
0.393 mol/L.
Explanation:
The following data were obtained from the question:
Number of mole of NaOH = 0.550 mol
Volume of solution = 1.40 L
Molarity of NaOH =.?
Molarity of a solution is simply defined as the mole of solute per unit litre of the solution. Mathematically, it is expressed as:
Molarity = mole /Volume
With the above formula, we can obtain the molarity of the NaOH solution as follow:
Number of mole of NaOH = 0.550 mol
Volume of solution = 1.40 L
Molarity of NaOH =.?
Molarity = mole / Volume
Molarity of NaOH = 0.55 / 1.4
Molarity of NaOH = 0.393 mol/L
Thus, the molarity of the NaOH solution is 0.393 mol/L.
Answer:
A. Soaps react with ions in hard water to create a precipitate.
B. Soaps are both hydrophobic and hydrophilic.
D. Soaps should be weakly alkaline in solution.
Explanation:
A. Hard water contains <u>magnesium and calcium minerals</u> like calcium and magnesium carbonates, sulfates and bicarbonates. As soon as these minerals come in contact with soap their ions like Mg²⁺ & Ca²⁺ form precipitates.
B. Soap are both hydrophilic and hydrophobic. They reason why they exhibit both the properties is really important for their functionality. The hydrophobic part of soap makes interaction with oil/dust particles while the hydrophilic part makes interaction with water. When the cloth is rinsed the dirt/soap particles are removed from the dirty clothes thereby making them clean.
C. Soaps have alkaline pH i.e. more than 7 that is why they have bitter taste.
<u>Answer:</u> The freezing point of solution is 2.6°C
<u>Explanation:</u>
To calculate the depression in freezing point, we use the equation:

Or,

where,
= 
Freezing point of pure solution = 5.5°C
i = Vant hoff factor = 1 (For non-electrolytes)
= molal freezing point depression constant = 5.12 K/m = 5.12 °C/m
= Given mass of solute (anthracene) = 7.99 g
= Molar mass of solute (anthracene) = 178.23 g/mol
= Mass of solvent (benzene) = 79 g
Putting values in above equation, we get:

Hence, the freezing point of solution is 2.6°C