Answer:
Central metal oxidation state: +2
Coordination number: 6
Overall charge: -2
Explanation:
For the ion complex:
Na₂[Cr(NH₃)₂(NCS)₄]
The central metal is chromium, with NH₃ and NCS as the ligands.
NH₃ acts as a neutral ligand, while NCS carries a negative charge.
The entire complex has a charge of:
2Na⁺ + [Cr(NH₃)₂(NCS)₄]⁻² → -2
Since each NCS contributes -1 and there are four NCS, the Cr must possess an oxidation state of +2 to achieve an overall charge of -2.
With 2 NH₃ and 4 NCS attached, the coordination number sums to 2+4 = 6
I trust this clarifies the matter!
A secondary alkyl halide would be characterized by having a carbon atom connected to two other carbon atoms, with bromine attached to that carbon.
Therefore, bromo-hexane qualifies as a 2-degree or secondary alkyl halide
The mass of hydrogen is 16.0 oz. To convert 16.0 oz of hydrogen into pounds, we utilize the conversion factor 1 lb = 16 oz. Next, we convert pounds to grams using the factors 1 kg = 2.2 lb and 1 kg = 1000 g. The heat of combustion for hydrogen is 142 J/g, and we will calculate the heat produced by combusting 16.0 oz.
FeCl₃ reacts frequently with phenolic compounds.
I hope this is useful!!
a) ΔH°rxn = -9.2kJ/mol
b) ΔH°rxn = -9.2kJ/mol
Explanation:
By applying Hess's law, the reaction enthalpy ΔH can be calculated from the enthalpies of formation of the reactants and products involved, thus:
ΔH°rxn = ∑(BE(reactants)) − ∑(BE(products)).
Alternatively, it can be expressed as:
ΔH°rxn = ∑(nΔH°f (products)) − ∑(mΔH°f (reactants)).
For the given reaction:
H₂(g) + I₂(g) → 2HI(g)
a) Using the first equation, we find:
ΔH°rxn = ΔH (H-H) + ΔH (I-I) - 2ΔHBE (H-I)
= 436.4kJ + 151kJ - 2×298.3kJ.
After the calculation, ΔH°rxn is determined to be -9.2kJ/mol.
b) Based on the second equation:
ΔH°rxn = 2ΔH°f (HI) − ΔH°f (H₂) - ΔH°f (I₂).
Substituting the values yields ΔH°rxn = 2×25.9kJ - 0kJ - 61.0kJ.
This also results in ΔH°rxn = -9.2kJ/mol.
