B. Gain information about the current state of the environment and ways to improve it.
The correct answer is a. This is because the pH of a solution is defined as -log10(concentration of H+ ions). An inverse logarithmic scale such as this means that a solution with a lower concentration of H+ ions will have a higher pH than one with a higher concentration. Therefore we know that the pH of the second sample will be higher than the first.
Since the logarithmic scale has the base 10, a change by 1 on the scale is a consequence of multiplication/division of the H+ concentration by a factor of 10. As the scale is inverse, this means that a decrease of concentration by factor 1000 is equivalent to increasing the pH by (1000/10) = 3.
The answer would be 2.0 x 10^-1
Familiar substances that sublime readily include iodine , dry ice , menthol, and camphor. Sublimation is occasionally used in the laboratory as a method for purification of solids, for example, with caffeine.
