I think it’s the third option but I’m not entirely sure
Density increases with the temperature, true.
Answer:
108.43 grams KNO₃
Explanation:
To solve this problem we use the formula:
Where
- ΔT is the temperature difference (14.5 K)
- Kf is the cryoscopic constant (1.86 K·m⁻¹)
- b is the molality of the solution (moles KNO₃ per kg of water)
- and<em> i</em> is the van't Hoff factor (2 for KNO₃)
We <u>solve for b</u>:
- 14.5 K = 1.86 K·m⁻¹ * b * 2
Using the given volume of water and its density (aprx. 1 g/mL) we <u>calculate the necessary moles of KNO₃</u>:
- 275 mL water ≅ 275 g water
- moles KNO₃ = molality * kg water = 3.90 * 0.275
- moles KNO₃ = 1.0725 moles KNO₃
Finally we <u>convert KNO₃ moles to grams</u>, using its molecular weight:
- 1.0725 moles KNO₃ * 101.103 g/mol = 108.43 grams KNO₃
To dissolve one substance, attractions between solute and solvent particles must be formed, steps involved are:
<h3><u>Formation of a solution:</u></h3>
- A physical process, not a chemical one, takes place when a solute and a solvent combine to produce a solution.
- In other words, by applying the right separation techniques, both the solute and the solvent may be recovered in chemically unaltered forms.
- It is claimed that two substances are entirely miscible when they combine to create a single homogenous phase in all ratios. Water and ethanol mix well, much like different gas combinations do.
- When two substances, like oil and water, are fundamentally insoluble in one another, they are said to be immiscible.
- We have already talked about several examples of gaseous solutions, such as the atmosphere of Earth.
- Thus, a system that has two or more compounds homogeneously (in a single phase) dissolved in it is called a solution. It is the homogenous mixture formed when a solute dissolves in a solvent.
To know more about solutions, refer to:
brainly.com/question/1616939
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