Asolution that contains equal numbers of hydrogen and hydroxyl ions would be called

The solutions, which have both hydrogen and hydroxide ions in equal number are neutral solution.

In a solution, if the hydrogen and the hydroxide ion are in equal number, they will mask each other's effect. So, all over, the effect of the hydrogen ion or hydroxide ion would be absent. So, the solution would indicate a pH of value 7.

Hence, the given blank can be filled with neutral.

answer: the blood-brain barrier is a layer of specialized membranes and cell processes designed to keep undesirable substances from passing from the bloodstream into the precious tissues of the brain. while the blood-brain barrier does keep most bad things out of the central nervous system, it is not impermeable.

explanation:

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