Quantitative observations include numerical data. Ex: 32 degrees, 10 inches, etc.
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Answer:
the entropy change for the surroundings when 1.62 moles of CH4(g) react at standard conditions is −8.343 J/K
Explanation:
The balanced chemical equation of the reaction in the question given is:
Using standard thermodynamic data at 298K.
The entropy of each compound above are listed as follows in a respective order.
Entropy of (CH4(g)) = 186.264 J/mol.K
Entropy of (O2(g)) = 205.138 J/mol.K
Entropy of (CO2(g)) = 213.74 J/mol.K
Entropy of (H2O(g)) = 188.825 J/mol.K
The change in Entropy (S) of the reaction is therefore calculated as follows:
= -5.15 J/mol.K
Given that :
the number of moles = 1.62 of CH4(g) react at standard conditions.
Then;
The change in entropy of the rxn 
= −8.343 J/K
Answer:
5 degrees required for ice
Answer:
C. I, III , IV
Explanation:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
