The molality is calculated using the following rule:
molality = number of moles of solute / kg of solvent
From the periodic table:
molar mass of lithium = 6.941 gm
molar mass of chlorine = 35.453 gm
molar mass of LiCl = 6.941 + 35.453 = 42.394 gm
number of moles found in 42 gm = mass / molar mass = 42 / 42.394 = 0.99
molality = 0.99 / 3.6 = 0.275 m
D — density
hope this helps !
Answer:
when electron emit the radiations it means it jumped to the lower energy level from higher energy level.
Explanation:
When electron jump into lower energy level from high energy level it loses the energy.
The process is called de-excitation.
Excitation:
When the energy is provided to the atom the electrons by absorbing the energy jump to the higher energy levels. This process is called excitation. The amount of energy absorbed by the electron is exactly equal to the energy difference of orbits.
De-excitation:
When the excited electron fall back to the lower energy levels the energy is released in the form of radiations. this energy is exactly equal to the energy difference between the orbits. The characteristics bright colors are due to the these emitted radiations. These emitted radiations can be seen if they are fall in the visible region of spectrum.
Answer:
5 moles of Fe
Explanation:
The equation of the reaction is;
2 Al(s) + Fe 2O 3(s) --> 2Fe (s) + Al 2O 3 (s)
Now;
1 mole of Fe2O3 require 2 moles of Al
3 moles of Fe2O3 requires 3 × 2/1 = 6 moles of Al
Hence Al is the limiting reactant.
If 2 moles of Al yields 2 moles of Fe
5 moles of Al yields 5 × 2/2 = 5 moles of Fe
Answer:
D. 1,950 g
Explanation:
I completed the test and it is the correct answer!