For the separation of the unknown mixture, you are instructed to isolate the amine followed by the acid and finally the neutral.
does the order matter? if not, what other orders could be followed?

Yes, it does. The neutral must be the last because it is 'left over'. However, the order of the acid and base/amine can be switched.

Explanation:

This is commonly known as the acid/base extraction method. It involves conducting simple acid/base reactions to separate the basic, acidic, and neutral compounds present in the given mixture. The neutral compounds generally do not react chemically with either the Brønsted acidic or basic compounds. The compounds present in the mixture can easily be separated. Therefore, for the given problem, the neutral must be the last because it is 'left over'. However, the order of the acid and base/amine can be switched.

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.

solute : a solute is a substance that is dissolved in another substance is known as a solvent. it is mixed with a special mixture know as homogeneous mixture.

solvent: a solvent is a substance that dissolved a solute, which results in a solution is known as solvent.