Answer:
a) Heterogeneous mixture (b) Homogenous mixture (c) Pure substance (d) Pure substance
Explanation:
Homogenous mixtures contains mixture of substances with similar proportions while Heterogenous mixture contains substances with a varying proportion.
The concentrations of a mixture at equilibrium are constant as a function of time because the <span>e forward reaction proceeds at the same rate as the reverse reaction.</span>
Answer:
II. The reaction is exothermic.
III. The enthalpy term would be different if the water formed was gaseous.
Explanation:
For the reaction:
C₂H₅OH(l) + 3O₂(g) → 2CO₂(g) + 3H₂O(l)
The ΔH is -1.37×10³ kJ. As the change in enthalpy is <0,<em> II. The reaction is exothermic.</em>
The ΔH formation of a compound is different if the chemical is in liquid or gaseous phase. For that reason: <em>III. The enthalpy term would be different if the water formed was gaseous.</em>
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I hope it helps!
Answer:
D. 60.3 kilometers per hour
Explanation:
Hello,
In this case, we first compute the miles in kilometres:

Then the minutes in hours:

Finally, the velocity:

Thus, answer is D. 60.3 kilometers per hour
Best regards.
Kb = [HA} [OH-] / [A-] where [A-] represents the concentration of CN- (.068M)
Kb = Kw / Ka = 1 x10-14 / 4.9 x 10-10 = 2 x 10-5
Since this is a salt solution which could be considered to have formed from the neutralization of a strong base (NaOH) and a weak acid (HCN), the Na+ will have no effect on the pH of the solution while the CN- ion will undergo hydrolysis:
CN- + H2O --> HCN + OH-
Based on this equation, the quantities of HCN and OH- produced must be the same and therefore [HCN]=[OH-]. We will set this equal to x.
Plugging into the original equation yields:
2 x 10-5 = x2 / .068 M
Solving for x yields 1.2 x 10-3 whidh is equal to the [OH-]
The pOH then is equal to -log (1.2x10-3) = 2.9
The pH of the solution would be 14 - 2.9 = 11.1