Answer:
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
Explanation:
One colligative property is the freezing point depression due the addition of a solute. The equation is:
ΔT=Kf*m*i
<em>Where ΔT is change in temperature = 0.400°C</em>
<em>Kf is freezing point constant of the solvent = 1.86°C/m</em>
<em>m is molality of the solution (Moles of solute / kg of solvent)</em>
<em>And i is Van't Hoff constant (1 for a nonelectrolyte)</em>
Replacing:
0.400°C =1.86°C/m*m*1
0.400°C / 1.86°C/m*1 = 0.215m
As mass of solvent is 280.0g = 0.2800kg, the moles of the solute are:
0.2800kg * (0.215moles / 1kg) = 0.0602 moles of solute must be added.
The mass of ethylene glycol must be added is:
0.0602 moles * (62.10g / mol) =
3.74g of ethylene glycol must be added to decrease the freezing point by 0.400°C
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The answer is a. <span>changes in nucleotides of a DNA molecule that affect the genetic message.</span>
Answer is: concentration of hydrogen iodide is 6 M.
Balanced chemical reaction: H₂(g) + I₂(g) ⇄ 2HI(g).
[H₂] = 0.04 M; equilibrium concentration of hydrogen.
[I₂] = 0.009 M; equilibrium concentration of iodine.
Keq = 1·10⁵.
Keq = [HI]² / [H₂]·[I₂].
[HI]² = [H₂]·[I₂]·Keq.
[HI]² = 0.04 M · 0.009 M · 1·10⁵.
[HI]² = 36 M².
[HI] = √36 M².
[HI] = 6 M.
At its discovery, benzene was recognized to be a unique unsaturated hydrocarbon because it either failed to react, by substitution with common reagents or reacted by addition that led to reactions with alkenes.
<h3>What are unsaturated hydrocarbons?</h3>
Unsaturated hydrocarbons are the hydrocarbons which have at least on double or triple carbon to carbon bond in its molecules.
All other hydrocarbons are unsaturated except for the alkanes and the cyclic alkanes.
Benzene is an aromatic compound which has a special six-carbon ring with are resonance structure reflecting the presence of three carbon-carbon bonds in its molecules.
The common reactions of unsaturated hydrocarbons are substitution and addition reactions.
However, benzene on its discovery did not undergo any of these reactions.
In conclusion, benzene showed a difference when compared with the common unsaturated hydrocarbons as it did not undergo either substitution or addition reactions.
Learn more about benzene at: brainly.com/question/6028840
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