What is the pH of a solution with an H+ ion concentration of 2.4E-4?

Which statement is true about the part of the electromagnetic spectrum that human eyes can detect? it contains only the colors of the rainbow and television waves. o it is divided into seven ranges of wavelengths. it contains ultraviolet, visible, and infrared light. it is divided into nine ranges of wavelengths.

Which solution is an example of a nonelectrolyte? a. iodine in hexane b. sodium nitrate in waterc. acetic acid in waterd. hydrogen chloride in water

The excretory system,need answers for all: )