Which of the following is a possible value for a ph?
a. 14.5
b. 12.0
c. -7.0
d. -14.0

b. 12.0

Explanation:

The pH scale measures the acidity or alkalinity of a substance . The pH scale ranges from 0 - 14. The pH value 7 depicts neutrality . The pH range 0 to 6 depicts acidity while 8 to 14 depict alkalinity.

The higher in concentration of the hydrogen ion , the lower the pH scale. 0 -2 depicts strong acidity contents. Generally, a low pH value signifies acidity.

The higher in concentration of the hydroxide ion, the higher the pH scale. High pH value depicts alkalinity content. The pH range 12 - 14 depicts strong alkalinity content.

When the hydrogen ion is equal to the hydroxide ion the solution becomes neutral. The pH value for neutrality is 7.  

The only possible pH measurement from the options is 12, Because pH scale ranges from 0 - 14.    The pH values have no negative value and it is not higher than 14.

c. because step up transformer steps up the input voltage i.e increases the input voltage  

the number of turns are greater on the secondary side of step up transformer  

transformer does not handle dc current