Answer:
Noble gases
Explanation:
The noble gases are non-metals that requires the highest amount of energy to remove an electron from their shells.
The reason for this difficult is that their electronic configuration confers a stable configuration them.
- The ionization energy is the energy required to remove the most loosely held electrons in an atom.
- Due to the special stability of noble gases, it is very difficult to remove electrons from an atom of noble gases.
Answer:
5 × 10^-4 L
Explanation:
The equation of the reaction is;
2KClO3 = 2KCl + 3O2
Number of moles of KClO3 = 13.5g/122.5 g / mol = 0.11 moles
From the stoichiometry of the reaction;
2 moles of KClO3 yields 3 moles of O2
0.11 moles of KClO3 yields 0.11 × 3/2 = 0.165 moles of oxygen gas
From the ideal gas equation;
PV= nRT
P= 85.4 × 10^4 KPa
V=?
n= 0.165
R= 8.314 J K-1 mol-1
T= 40+273 = 313K
V= 0.165 ×8.134 × 313/85.4 × 10^4
V=429.4/85.4 × 10^4
V= 5 × 10^-4 L
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%.