Answer:
the time required for one half of a sample of a radioisotope to decay
The correct answer is 0.44ml
For information, promethazine is a neuroleptic antihistamine inhibitor of H1 receptors of the phenothiazine family. It is a medicine used in the treatment of allergy (like rhinitis) and transient insomnia.
To respond to this exercise, it is necessary to cross-multiply.
In the antihistamine bottle solution:
25 mg corresponds to 1 ml
11 mg corresponds to: 11/25 = 0.44 ml of the solution.
This 0.44ml is taken from the bottle and put to the syringe.
The base is H2O because it is accepting an H+ ion.
(2) gains 12 moles of electrons, easy, because it must retain the same mass in a balanced equation, so if there is no exterior mention of any electrons, such as the notation +12e-, than we must assume that the Oxygen took it at any rate.
