Answer: 
Explanation:
Lattice energy : It is defined energy released when ions combine together in a gaseous phase to form a compound. it is energy possessed by the crystal lattice of a compound. Denoted by symbol
.
, energy is absorbed while forming of the lattice
, energy is release while forming of the lattice

One mole of sodium ion when combines with one mole chloride ion release 786 kJ of energy.
Explanation:
Equation of the reaction:
Br2(l) + Cl2(g) --> 2BrCl(g)
The enthalpy change for this reaction will be equal to twice the standard enthalpy change of formation for bromine monochloride, BrCl.
The standard enthalpy change of formation for a compound,
ΔH°f, is the change in enthalpy when one mole of that compound is formed from its constituent elements in their standard state at a pressure of 1 atm.
This means that the standard enthalpy change of formation will correspond to the change in enthalpy associated with this reaction
1/2Br2(g) + 1/2Cl2(g) → BrCl(g)
Here, ΔH°rxn = ΔH°f
This means that the enthalpy change for this reaction will be twice the value of ΔH°f = 2 moles BrCl
Using Hess' law,
ΔH°f = total energy of reactant - total energy of product
= (1/2 * (+112) + 1/2 * (+121)) - 14.7
= 101.8 kJ/mol
ΔH°rxn = 101.8 kJ/mol.
The mass of water is the same as the mass of ice
Answer:
Hydrosulfuric acid will act as limiting reactant.
Explanation:
Given data:
Mass of iron(III) chloride = 3243.0 g
Mass of hydrosulfuric acid = 511.8 g
Limiting reactant = ?
Solution:
Chemical equation:
2FeCl₃ + 3H₂S → Fe₂S₃ + 6HCl
Number of moles of iron(III) chloride:
Number of moles = mass/molar mass
Number of moles = 3243.0 g/ 162.2 g/mol
Number of moles = 20 mol
Number of moles of hydrosulfuric acid:
Number of moles = mass/molar mass
Number of moles = 511.8 g/ 34.1 g/mol
Number of moles = 15 mol
Now we will compare the moles of both reactant with products
FeCl₃ : Fe₂S₃
2 : 1
20 : 1/2 ×20 = 10
FeCl₃ : HCl
2 : 6
20 : 6/2 ×20 = 60
H₂S : Fe₂S₃
3 : 1
15 : 1/3 ×15 = 5
H₂S : HCl
3 : 6
15 : 6/3 ×15 = 30
Hydrosulfuric acid producing less number of moles of product thus, it will act as limiting reactant.