When recovering the aqueous and organic layers from the separatory funnel . (Select all that apply.) A. the lower layer should be allowed to drain through the tap B. the stopper must be removed in order to allow the funnel to drain C. the stopper must be kept in place during draining D. the aqueous layer should always be poured from the top, regardless of which layer it is E. magnesium sulfate should be added to the funnel before pouring, to dry the organic layer

Option A and C applies

- A. the lower layer should be allowed to drain through the tap

- C. the stopper must be kept in place during draining

Explanation:

Since aqueous and organic substances do not mix, they form a layer between them. Hence, require a separatory funnel with a stopper to recover each fraction effectively.

First, the lower fraction (aqueous) is recovered when the stopper is opened to allow draining through the tap into a well labelled beaker

Second, the stopper must be kept in place to shut the tap once the lower fraction has been collected. So, the organic fraction remains in the seperating funnel

Thus, Option A and C applies

answer : one can design an experiment using a liquid and an additive that can be added to the liquid and observe the chemical changes in the reaction species.

one would need a beaker which is filled with a known amount of the liquid in which thermometer is placed to measure the temperature changes; after addition of the additive to the liquid solution one can note down the temperature change and find whether the reaction is endothermic or exothermic in nature. by subtracting the initial temperature value with the final temperature one can find the temperature changes.

various combinations of liquid and additive can be used. liquid in this case can be a known quantity of water and additives can be epsom salt or without epsom salt the experiment can be conducted to notice the changes. water and ice, hydrogen peroxide and dry yeast, vinegar and baking soda,etc.