Answer:
The answer is A, It shows an exothermic overall reaction.
Explanation:
Electrons in sigma <span>bonds remain localized between two atoms. Sigma </span><span>bond results from the formation of </span><span>a molecular orbital </span><span>by the end to </span><span>end overlap of atomic </span>orbitals. Electrons<span> in pi</span> bonds can become delocalized between more than two atoms. Pi bonds result from the formation of molecular orbital by side to side overlap of atomic orbitals.
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Answer:
A. synthesis
Explanation:
The reaction given is a synthesis reaction in which two substances combines to give a product.
In this reaction:
4Fe + 3O₂ → 2Fe₂O₃
The reaction involves the formation of a single product from two or more reactants.
The formation of a compound from union of the constituent elements also falls into this category of reaction.
Answer:
i = 2.79
Explanation:
The excersise talks about the colligative property, freezing point depression.
Formula to calculate the freezing point of a solution is:
Freezing point of pure solvent - Freezing point of solution = m . Kf . i
Let's replace data given. (i = Van't Hoff factor, numbers of ions dissolved in solution)
48.1°C - 44°C = 0.15 m . 9.78°C/m . i
4.1°C / (0.15 m . 9.78°C/m) = i
i = 2.79
In this case, numbers of ions dissolved can decrease the freezing point of a solution, which is always lower than pure solvent.