Acids are chemical substances that dissolve in water to produce hydrogen ions(H+ ) as the only positively charged ions(cations). In other words, acids are also termed as proton donors.
On the other hand, bases also known as alkali are chemical substances that dissolve in water yielding hydroxyl ions(OH- ) as the only negatively charged ions(anions).
How do we know if a liquid is an acid
Physically, there are various simple practices we can carry out to ascertain whether a liquid sample is alkaline or acidic. Acids tend to assume a sour taste. However, it is not advisable to taste as in high concentrations acids can be highly corrosive. Also, it should be noted that most acids are liquid in nature at room temperature of 250C.
On the other hand, alkalis physically have a bitter taste. The challenge is in differentiating between bitterness and a sour substance. In addition to that bases have a soapy feeling- that tells why substances such as Sodium hydroxide is used in the manufacture of soaps.
The significance of pH meters in determining acidity and alkalinity
You never will understand pH meters without understanding what pH means. The pH of a substance is just an indicator of the number of cations(H+) the substance forms in s certain specified volume of water and this measures alkalinity and acidity in liquids that you may want to consume.
There are many chemically designed pH meters that are used in determining acidity and alkalinity of different substances. They are of different kinds as some are simple and cheap, while others are specifically designed for laboratory and in some cases industrial use. These meters are designed in such a way that they produce results either in an analog way or digitally through the use of computer UIs.
Types of pH meters
As mentioned earlier there are a lot of these:
Specialty meters and probes are mostly designed for use in harsh conditions of environments.
There are holographic pH sensors that can be used to measure the pH of colored substances hence making use of pH indicators. As a result of this, it is possible to determine the pH value more easily.
Solid state electrode pH meters- Built mainly around Ion Selective Field Effect Transistors, these pH meters are relatively less bulky compared to the standard glass electrode ones.
How does it work?
A pH meter borrows from the functionalities of a voltmeter. It should be understood that the of cations in an acidic solution is far off more than those of an alkaline solution. As a result of this, acids conduct current with a greater potential than bases.
More pH meters come fully calibrated for ease of usage.