Freezing point depression depends of the number of particles of the solute in the solution.
1)Pure water have highest freezing point. All other solutions with given solutes will have lower temperatures.
2) The more particles of the solute in the solution the lower freezing point is going to be.
<span>b. 1.0 m NaCl ( dissociates and give 2 mol ions (1 mol Na⁺ and 1 mol Cl⁻))
c. 1.0 m K3PO4 (</span>dissociates and give 4 mol ions (3 mol K⁺ and 1 mol PO4³⁻)<span>
d. 1.0 m CaCl2 (</span>dissociates and give 3 mol ions (1 mol Ca²⁺ and 2 mol Cl⁻))<span>
e. 1.0 m glucose (c6h12o6) (glucose does not dissociate, and solution have
1 mole of particles of the solute(glucose))
The largest number of particles has </span>1.0 m K3PO4 solution, and it is has lowest freezing point . Answer is C.
The solution before dilution and after dilution contains same number of moles, and water is added for dilution.
Option B
<h3><u>Explanation:</u></h3>
Suppose before dilution, the solution contains x moles of KCl in Y liter of water. Now as the concentration got halved, then the solution contains x moles of KCl in 2Y kiters of solution. So the number of moles of KCl in the solution remained constant.
Again, as the solution is diluted to half of the concentration, water must have been added with the solution to make it dilute.
Answer:
- <u>TRUE:</u> <em>Percent concentration is one of the most common and basic concentration measurement used by general public</em>
Explanation:
In chemistry there are many <em>concentration measurements</em> used to describe the mixtures. Some of them are, percent, molarity, molality, and molar fraction, among others.
Percent concentration is a popular one because it is commonly understood and used by the non specialist people, i.e. general public.
The percent concentration of a component is defined as: (amount of component in the mixture / amount of mixture) × 100.
The amounts may be measured in mass units (e.g grams) or volume units (e.g. mililiters).
For solutions, mass percent concentration is:
- % = (mass of solute / mass of solution) × 100.
And voluem percen contration is:
- % = (volume of solute / volume of solution) × 100
Since percentage is used in many profesional and personal activities, most persons use it.
For example, rubbing alcohol, that everyone buys in pharmacies, is 70%; vinager, used in the food, is acetic acid at 5% - 8%.
I believe it would be 7.731. x 10^5? That is if they want you to evaluate.
