I'm not sure about number 1 or number 6, but I know that 3 is nucleic acid and 5 is solution.
So that other people can replicate the experiment.
if someone does an experiment and finds something interesting, they might publish the details of the experiment, so that other scientists may replicate it and verify that the experiment is real.
A negative charge exists because of the electronegativity of oxygen.
Hope this helps!! & have a great day!!!!!!!
