Answer : The enthalpy change for the reaction is, 97.7 kJ
Explanation :
According to Hess’s law of constant heat summation, the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps.
According to this law, the chemical equation can be treated as ordinary algebraic expression and can be added or subtracted to yield the required equation. That means the enthalpy change of the overall reaction is the sum of the enthalpy changes of the intermediate reactions.
The given main chemical reaction is,

The intermediate balanced chemical reaction will be,
(1)

(2)

(3)

Now we are multiplying reaction 1 by 2 and reversing reaction 3 and then adding all the equations, we get :
(1)

(2)

(3)

The expression for enthalpy of main reaction will be,



Therefore, the enthalpy change for the reaction is, 97.7 kJ
I believe it is B writing chemical formulas
Kilo: a prefix used on metric units to indicate a multiple of 1000. For example 1kg = 1000 g
Answer:
1s2 2s2 2p6 3s2 3p6
Explanation:
Chlorine is a groups 17 element. The halogens for ions by accepting one electron to form univalent negative ions.
Since chlorine normally contains seventeen electrons, the chloride ion consists of eighteen electrons.
Hence the electronic configuration of chlorine ion is; 1s2 2s2 2p6 3s2 3p6.
Answer:
CN^- is a strong field ligand
Explanation:
The complex, hexacyanoferrate II is an Fe^2+ specie. Fe^2+ is a d^6 specie. It may exist as high spin (paramagnetic) or low spin (diamagnetic) depending on the ligand. The energy of the d-orbitals become nondegenerate upon approach of a ligand. The extent of separation of the two orbitals and the energy between them is defined as the magnitude of crystal field splitting (∆o).
Ligands that cause a large crystal field splitting such as CN^- are called strong field ligands. They lead to the formation of diamagnetic species. Strong field ligands occur towards the end of the spectrochemical series of ligands.
Hence the complex, Fe(CN)6 4− is diamagnetic because the cyanide ion is a strong field ligand that causes the six d-electrons present to pair up in a low spin arrangement.