I believe that the best answer among the choices provided by the question is <span>It is the difference between reactant energy and maximum energy.
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Hope my answer would be a great help for you. If you have more questions feel free to ask here at Brainly.
Answer:
The molar mass of the organic solid is 120.16 g/mol.
The molecular formula of an organic solid is 
Explanation:
Let the molecular mass of an organic solid be 


where,
=Elevation in boiling point = 
Mass of organic solid= 0.561 g
Mass of diphenyl = 24.9 g = 0.0249 kg (1 kg = 1000 g)
= boiling point constant = 8.00 °C/m
m = molality
Now put all the given values in this formula, we get



Percentage of carbon in an organic solid = 40.0%

x = 4.0
Percentage of hydrogen in an organic solid = 6.7%

y = 8.0
Percentage of hydrogen in an organic solid = 6.7%

y = 4.0
The molecular formula of an organic solid is 
I would say the most correct answer is Kilo, as in kilometers. The store would certainly not be milli, or millimeters away from you, would it now? :)
Hope this helps!
Answer is: 4) The same subscripts are on each side of the equation.
For example, balanced chemical reaction:
2Mg + O₂ → 2MgO.
1) The same number of atoms is on each side of the equation: two magnesium atoms and two oxgen atoms.
2) The formulas for all substances are correct: in magnesium oxide (MgO), magnesium has oxidation number +2 and oxygen -2, so formula is good, because compound must be neutral.
3) The same mass is represented on each side of the equation: because there is same number of atoms, the mass is the same.
4) The same subscripts are on each side of the equation: oxygen does not have same subscripts.
Na is the symbol for sodium.