The purpose<span> of preparing </span>Set-up<span> _ is to act as a </span>control set-up<span> to ensure that the (measured variable) is only caused by the(changed variable) and not any other variables in the experiment.</span>
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.
Isotopes are forms of the same elements which contain equal number of protons but different number of nucleus in their nuclei, thus the differ in relative atomic mass but they have same chemical properties. The mass number is the summation of number of proton and number of neutron of an atom. If the mass number is known, then one need to know the number of proton in the atom in order to calculate for the number of neutron.
The answer to your question big man would be E
It would be 36 because the atomic mass of carbon is 12
