Answer:
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Explanation:
The lowering of the freezing point of a solvent is a colligative property ruled by the formula:
Where:
- ΔTf is the lowering of the freezing point
- Kf is the molal freezing constant of the solvent: 1.86 °C/m
- m is the molality of the solution
- i is the van't Hoff factor: the number of particles (ions) per unit of ionic compound.
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<u>a) molality, m</u>
- m = number of moles of solute/ kg of solvent
- number of moles of CaI₂ = mass in grams/ molar mass
- number of moles of CaI₂ = 25.00g / 293.887 g/mol = 0.0850667mol
- m = 0.0850667mol/1.25 kg = 0.068053m
<u>b) i</u>
- Each unit of CaI₂, ideally, dissociates into 1 Ca⁺ ion and 2 I⁻ ions. Thus, i = 1 + 2 = 3
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<u>c) Freezing point lowering</u>
- ΔTf = 1.86 °C/m × 0.068053m × 3 = 0.3797ºC ≈ 0.380ºC
<h2>I have problems to upload the full answer in here, so I attach a pdf file with the whole answer.</h2>
Answer:
pH is an index of how many protons, or hydrogen ions (H+) are dissolved and free in a solution. The pH scale goes from 0 to 14. A fluid with a pH of 7 is neutral. Below 7, it is acidic; above 7, it is alkaline.
The more below or above 7 a solution is, the more acidic or alkaline it is. The scale is not linear—a drop from pH 8.2 to 8.1 indicates a 30 percent increase in acidity, or concentration of hydrogen ions; a drop from 8.1 to 7.9 indicates a 150 percent increase in acidity. Bottom line: Small-sounding changes in ocean pH are actually quite large and definitely in the direction of becoming less alkaline, which is the same as becoming more acidic.
If you think about it, we use descriptive words like this all the time. A person who stands 5’5” tall and weighs 300 pounds isn’t thin. If he loses 100 pounds, he still won’t be thin, but he will be thinner than he was before he went on the diet. (And we are more likely to comment that he’s looking trimmer than to say he’s not as fat as he used to be.)
134.5 grams in 4.5 moles of Li2O (lithium oxide).
Answer:
Ethanol is completely miscible due to <u><em>presence</em></u> of Hydrogen bonding.
Ethanethiol is partially miscible due to <u><em>absence</em></u> of Hydrogen Bonding.
Explanation:
The miscibility of liquids depend upon the intermolecular interactions between the two liquids. The stronger the intermolecular interactions the more miscible will be the liquids.
Among the two given examples, Ethanol is more miscible in water because it exhibits hydrogen bonding which is considered the strongest intermolecular interaction. Hydrogen bonding occurs when the hydrogen atom is bonded to more electronegative atoms like Fluorine, Oxygen and Nitrogen. In this way the hydrogen atom gets partial positive charge and the electronegative atom gets partial negative charge. Hence, these partial charges results in attracting the opposite charges on other surrounding atoms.
While, in case of Ethanethiol the hydrogen atom is not bonded to any high electronegative atom hence, there will be no hydrogen bonding and therefore, there will be less interactions between the neighbour atoms.
Answer: Because it is a giant fire ball