An old penny rusting, remember you can’t undo a chemical change
evaporation systems allow for an endless source of water. you can grab cups of water straight from the sea or even a lake. the use of evaporation allows for you to drink water thats even healthier than getting it from a cloud and it will leave all of the bad parts that used to be in the water in the first container you pour into. this system is most useful in hot climates such as places near the equator.
PH scale is used to determine how acidic, basic or neutral a solution is
pH can be calculated using the H₃O⁺
ph can be calculated as follows
pH = - log[ H₃O⁺]
[H₃O⁺] = 1 x 10⁻⁹
pH = - log [1 x 10⁻⁹]
pH = 9
pH of solution is 9
B . microscope
this is the answer .