Answer:
Molar mass of unknown solute is 679 g/mol
Explanation:
Let us assume that the solute is a non-electrolyte.
For a solution with non-electrolyte solute remains dissolved in it -
Depression in freezing point of solution, 
where, m is molality of solute in solution and
is cryogenoscopic constant of solvent.
Here 
If molar mass of unknown solute is M g/mol then-

So, 
so, M = 679 g/mol
there's no question on here
<h3><u>Answer;</u></h3>
Acids; HCl and HC5H5N+
Bases; C5H5N and Cl-
<h3><u>Explanation;</u></h3>
- According to Bronsted-Lowry Theory an acid is a proton or hydrogen ion donor while a base is a proton or a hydrogen ion acceptor.
- In this case,<u> both HCl and HC5H5N+ are acids</u> as <u>they are donors of hydrogen ions</u>. HCl is an acid to the forward reaction while HC5H5N+ is a acid to the reverse reaction.
- On the other hand, <u>C5H5N and Cl- are bases</u>, <u>they are acceptors of hydrogen ions</u>. Cl- is a base in the reverse reaction while C5H5N is a base in the forward reaction.
The number of C2H5OH in a 3 m solution that contain 4.00kg H2O is calculate as below
M = moles of the solute/Kg of water
that is 3M = moles of solute/ 4 Kg
multiply both side by 4
moles of the solute is therefore = 12 moles
by use of Avogadro law constant
1 mole =6.02 x10^23 molecules
what about 12 moles
=12 moles/1 moles x 6.02 x10^23 = 7.224 x10^24 molecules
When utilizing the gravimetric method, it is crucial to completely dissolve your sample in 10 mL of water. A quantitative technique called gravimetric analysis employs the selective precipitation of the component under study from an aqueous solution.
A group of techniques known as gravimetric analysis are employed in analytical chemistry to quantify an analyte based on its mass. Gravimetric analysis is a quantitative chemical analysis technique that transforms the desired ingredient into a substance (of known composition) that can be extracted from the sample and weighed. This is a crucial point to remember.
Gravimetric water content (g) is therefore defined as the mass of water per mass of dry soil. To calculate it, weigh a sample of wet soil, dry it to remove the water, and then weigh the dried soil (mdry). Dimensions of the sample Water is commonly forgotten despite having a density close to one.
To know more about gravimetry, please refer:
brainly.com/question/18992495
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