Answer:
for X is -1.20 V
Explanation:
Oxidation:
[
]
reduction: 
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overall:
So, 
or, 
or, 
So,
for X is -1.20 V
A significant figure is every symbol that made the number itself.
In this case, the number 40.00 has four figures but only two of them are significant 40, this is because you haven't got any more decimals than the first zero.
If you have a case with zeros in front, you take to the first non zero digits.
For example, 0.071004 you wold express as 0.071 and those 7, and 1 are the significant ones.
solution:
Hydration is the addition of water; hydrogenation is the addition of hydrogen.
desire rxn: _C4H6(g) + 2 H2(g)-----> C4H10(g)___dHhy = ??
knowns:
__________C4H6 + 11/2 O2 --------> 4CO2 + 3H2O______dHox = -2540.2 kJ/mole
__________4CO2 + 5H2O -----------> C4H10 + 13/2 O2___-dHox = 2877.6 kJ/mole
___________2(1/2 O2 + H2 -------------> H2O)___________2*dHox = 2(-285.8 kJ/mole)
Basic mathematics is a prerequisite to chemistry – I just try to help you with the methodology of solving the problem
The ionic character of any compound depend on the lattice energy as well as the electronegativity of element present in that compound.
More would be the lattice energy more would be ionic nature of that compound.
The lattice energy of any compound is inversely proportional to the ionic radii cation and anion.
In given case the ionic radii of oxide in both oxides would be equal therefore the lattice energy only depend on the ionic radii of cation.
As the radii of Magnesium less then radii of lithium therefore lattice energy of Magnesium oxide would be more than lithium oxide.
Hence, MgO would be more ionic in nature than 
Answer:
N2I6 = 789 g
N2I6 = 8.2x1022 molecules N2I6 x 1 mole/6.02x1023 molecules = 1.36x10-1 moles = 0.136 moles
N2I6=0.136molesx789g/mole=107g=110g
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Hope this helps, have a BLESSED AND WONDERFUL DAY!
- Cutiepatutie ☺❀❤