Please read question/answer choices carefully and answer ALL questions with a clear and simple explanation. Incorrect or Incomplete answers will not be given any credit (thumbs down). Thank you!Q1. Predict the order of elution of a mixture of benzyl alcohol, biphenyl, benzoic acid, and methyl benzoate from an Alumina column in column chromatography. AND WHY (SIMPLE EXPLANATION)Q2. Calculate the percent yield of Methyl nitrobenzoate, if 6 grams of Methyl benzoate produced 3 grams of Methyl nitrobenzoate during the nitration experiment. Q3. According to the news, the Mississippi River is polluted with toxic Dioxin. You have a pure sample of Dioxin. How do you determine that the news is true or not?Q4. Explain the Retention time, in GC. What will happen to retention time, if you increase the detector temperature?

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

the density of gold = 19.3 g/cm3

the relation between density and mass and volume is

density = mass / volume

given :

mass of gold = 13 g

density = 13g / volume = 19.3

volume = 13 /19.3 = 0.67 cm^3

thus volume of gold nugget = 0.67 cm^3