Hydronium ion is H3O(+)
pH is log 1 / [H3O(+)] = - log [H3O(+)]
Rainfall: pH = 5.0 = - log [H3O(+)] => [H3O(+)] = -antilog (- 5.0) = 10^-5
Water; pH = 7.0 = - log [H3O(+)] => [H3O(+)] = - antilog (-7.0) = 10^ -7
Divide hidronium conentration of rainfall by hidrodium concentration of water:
10^-5 / 10^-7 = 10^2 = 100.
Then, hidronium concentration in rainfall is 100 times hidronium concentration in water.
Answer: option a. 100 times.
acid
when a metal hydroxide reacts with acid it forms a salt and water, for example:
lithium hydroxide + hydrochloric acid → lithium chloride (the salt) + water
If a lightbulb is powered by something like a C battery, the chemical energy from the battery acid is transformed into light and heat energy in the lightbulb. If it's powered by a potato (a common science project for kids) the stored chemical energy that the potato gets from sunlight does the same thing as the acid.
