Answer: Option (a) is the correct answer.
Explanation:
Entropy means the degree of randomness present within the molecules of an object.
When a substance is present in a solid state then its molecules are held together because of strong intermolecular forces of attraction.
As a result, molecules are not able to move freely and therefore, there will be no randomness.
But when a substance changes into liquid state then its molecules mover further apart from each other due to gain in kinetic energy. Hence, randomness increases.
On the other hand, when a substance moves from liquid to gaseous state then its molecules gain more kinetic energy due to which there will be high degree of randomness.
Therefore, as the products in the given reaction are present in liquid and gaseous state. So, this means that there has been an increase in entropy.
A decrease in entropy is represented by negative sign and an increase in entropy is represented by a positive sign.
Thus, we can conclude that the sign of for the given reaction is > 0.
Answer:
Explanation:
4FeS₂ + 11O₂ → 2Fe₂O₃ + 8SO₂.
4 moles of FeS₂ reacts with 11 moles of O₂
8 moles of FeS₂ reacts with 22 moles of O₂
Moles of O₂ available is 15 .
So O₂ is in short supply .
So O₂ is the limiting reagent.
Option (c) is the right choice.
Answer:
Rb
Explanation:
Second ionization energy is the energy required for the removal of the second loosely bonded valence electron from an isolated gaseous atom.
The given elements:
Rb , Sr, Y and Zr
These are the elements of the fifth period.
The electronic configuration of Rb -
The electronic configuration of Sr -
The electronic configuration of Y -
The electronic configuration of Zr -
<u>When one electron is removed from Rb, the cation attains the noble gas configuration due to which the removal of second electron from Rb is very very difficult. Thus, Rb has the largest second ionization energy.</u>
The values of the second ionization of these elements are:
Rb = 2633 kJ/mol
Sr = 1064.2 kJ/mol
Y = 1180 kJ/mol
Zr = 1270 kJ/mol
<span>In order for us to see an object that is non-luminous, it must reflect some of the light it receives from a luminous source, such as the Sun. Most of the objects we see, such as cars, clouds or even the Moon, are not luminous; it is just that they reflect sunlight</span>
A.)
dG = -(0.008314)(348K) (1.5 * 10-5)
dG = -(0.008314)(348K (-11.107)
dG = 32 kJ/mol (rounded from 32.14)
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B.)
AgCl(s) >>>> Ag+ and Cl-
<span>Ksp = {Ag+}{Cl-}
</span><span>1.5 * 10-5 = {Ag+}{Cl-}
</span>1.5 * 10-5 = {X}{X}
<span>X2 = 1.5 x 10-5
</span>X={Ag+}{Cl-}
Sol / AgCl = 3.873E-3 litres/moles
<span>(3.873E-3 moles AgCl/Litre) (143.32 g AgCl / mol)= 0.56g AgCl</span>