Explanation:
The given data is as follows.
Weight of solute = 75.8 g, Molecular weight of solute (toulene) = 92.13 g/mol, volume = 200 ml
- Therefore, molarity of toulene is calculated as follows.
Molarity = 
= 
= 4.11 M
Hence, molarity of toulene is 4.11 M.
- As molality is the number of moles of solute present in kg of solvent.
So, we will calculate the molality of toulene as follows.
Molality = 
= 
= 8.6 m
Hence, molality of given toulene solution is 8.6 m.
- Now, calculate the number of moles of toulene as follows.
No. of moles = 
= 
= 0.8227 mol
Now, no. of moles of benzene will be as follows.
No. of moles = 
= 
= 1.2239 mol
Hence, the mole fraction of toulene is as follows.
Mole fraction = 
= 
= 0.402
Hence, mole fraction of toulene is 0.402.
- As density of given solution is 0.857
so, we will calculate the mass of solution as follows.
Density = 
0.857
=
(As 1
= 1 g)
mass = 171.4 g
Therefore, calculate the mass percent of toulene as follows.
Mass % = 
= 
= 44.22%
Therefore, mass percent of toulene is 44.22%.
<u>Answer:</u>
<u>For a:</u> The edge length of the unit cell is 314 pm
<u>For b:</u> The radius of the molybdenum atom is 135.9 pm
<u>Explanation:</u>
To calculate the edge length for given density of metal, we use the equation:

where,
= density = 
Z = number of atom in unit cell = 2 (BCC)
M = atomic mass of metal (molybdenum) = 95.94 g/mol
= Avogadro's number = 
a = edge length of unit cell =?
Putting values in above equation, we get:
![10.28=\frac{2\times 95.94}{6.022\times 10^{23}\times (a)^3}\\\\a^3=\frac{2\times 95.94}{6.022\times 10^{23}\times 10.28}=3.099\times 10^{-23}\\\\a=\sqrt[3]{3.099\times 10^{-23}}=3.14\times 10^{-8}cm=314pm](https://tex.z-dn.net/?f=10.28%3D%5Cfrac%7B2%5Ctimes%2095.94%7D%7B6.022%5Ctimes%2010%5E%7B23%7D%5Ctimes%20%28a%29%5E3%7D%5C%5C%5C%5Ca%5E3%3D%5Cfrac%7B2%5Ctimes%2095.94%7D%7B6.022%5Ctimes%2010%5E%7B23%7D%5Ctimes%2010.28%7D%3D3.099%5Ctimes%2010%5E%7B-23%7D%5C%5C%5C%5Ca%3D%5Csqrt%5B3%5D%7B3.099%5Ctimes%2010%5E%7B-23%7D%7D%3D3.14%5Ctimes%2010%5E%7B-8%7Dcm%3D314pm)
Conversion factor used:
Hence, the edge length of the unit cell is 314 pm
To calculate the edge length, we use the relation between the radius and edge length for BCC lattice:

where,
R = radius of the lattice = ?
a = edge length = 314 pm
Putting values in above equation, we get:

Hence, the radius of the molybdenum atom is 135.9 pm
Heavy rainfall causes a landslide. Hence, option A is correct.
<h3>What is a landslide?</h3>
A landslide is defined as the movement of a mass of rock, debris, or earth down a slope.
Water can trigger landslides and mudslides because it alters the pressure within the slope, which leads to slope instability.
Consequently, the heavy water-laden slope materials (soil, rock, etc.) will succumb to the forces of gravity.
Hence, option A is correct.
Learn more about the landslide here:
brainly.com/question/16151931
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