Answer:
-252.5 kJ/mol = ΔH H2O(g)
Explanation:
ΔH Fe2O3 = -825.5kJ/mol
ΔH H2 = 0kJ/mol
ΔH Fe = 0kJ/mol
Based on Hess's law, ΔH of a reaction is the sum of ΔH of products - ΔH of reactants. For the reaction:
Fe2O3(s) + 3 H2(g) →2Fe(s) + 3 H2O(g)
ΔHr = 67.9kJ/mol = 3*ΔH H2O + 2*ΔHFe - (ΔH Fe2O3 + 3*Δ H2)
67.9kJ/mol = 3*ΔH H2O + 2*0kJ/mol - (ΔH -825.5kJ/mol + 3*Δ H2)
67.9 = 3*ΔH H2O(g) + 825.5kJ/mol
-757.6kJ/mol = 3*ΔH H2O(g)
<h3>-252.5 kJ/mol = ΔH H2O(g)</h3>
Answer:
the layer of a liquid or gaseous heat-transfer agent between the free stream and a heat-exchange surface. In this layer the temperature of the heat-transfer agent changes from that of the wall to that of the free stream
Explanation:
The Nitrogen (N) will have the greatest attraction for the chlorine electrons.
Answer: A) N
Explanation
The tendency or the ability to attract electrons is termed as electronegativity.
The electronegativity tend to increase from left to right in the periods and bottom to top in the groups of the periodic table. So it is known that the halogen group consists of the most electronegative elements.
Though chlorine has high electronegativity of 3.16, the electrons of chlorine can be attracted by other electronegative elements provided that their electronegativity should be in the range of the electronegativity of Cl.
So among the elements given, Nitrogen (N) has an electronegativity of 3.04, Phosphor (P) has an electronegativity of 2.19 and Arsenide electronegativity is 2.18.
Thus it can be seen that the electronegativity is maximum for Nitrogen among the three elements so it should have the greatest tendency to attract Cl electrons.
Answer:
Ammonium chloride, iron ,Sulphur and salt mixed together... they can be separated in the following methods.
1. Ammonium chloride is separated by sublimination... NC4CI is sublimable. Heat the mixture in a china dish and collect the funds of NC4CI (sublimable substance)
2. Bring a magnet close to the remaining mixture. Iron is magnetic substance and thus, it will be attracted towards the magnet. Iron is separated.
3. Sulphur is insoluble in water and salt is soluble. Add water to the remaining mixture and then wait for sedimentation. Separate the sulphur by decantation.
4. Heat the filtered salt solution to obtain salt.
