A pH meter is a scientific instrument that can be used to test and measure the acidity of both liquids and semi-solids. Such devices are commonly utilized in domains like chemistry, wine brewery, and a variety of other applications. Medical professionals mostly rely on the use of pH strips, which are different compared to their electronic counterparts.
One thing to keep in mind is that these products come in a variety of shapes and sizes and are made for different purposes.
Benchtop pH meters are by far some of the convenient models that we have found available these days, and some argue that they are among the most accurate gadgets in the line. Unfortunately, this type of design also tends to cost a pretty penny, and that’s why you’re likely to find it in labs and other places where the product is used for professional activities.
Smaller models can be used at home. Some compact varieties are so portable that they can even fit into your pocket. Every such gadget requires calibration either on occasion or before every use. You should also make sure that the probe, also known as the electrode, is clean and dry. You can use distilled water to get rid of any dust or other debris. You do, however, have to clean the electrode with care so as to avoid damaging it.
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How to determine pH with indicator strips
Using pH strips instead of an actual device is by far the most convenient and efficient method currently employed in labs. Of course, for other types of liquids, you may have to consider getting a real pH meter, but for urine and other bodily fluids, pH test strips can undoubtedly prove their worth.
The vast majority of the strips that you’ll find available for sale today are accurate, so there’s no need for you to go through a lot of trouble with regard to any kind of calibration. However, if you are feeling unsure about the strips you’ve purchased, we recommend starting by testing the pH of liquids you know the pH of. Note the color and then compare it to a scale.
On the same note, it is worth adding that the color scale made available by the pH test strip manufacturing brand is the one you should be using. Strips can vary in this sense from one company to the next, and the last thing you’d want to do is use an online color scale.
You wouldn’t believe the degrees of inaccuracy you need to deal with just because of the display of your computer. Stick to printed color scales, if you can.
What is a pH meter made of?
While there are several variations on this account, we have found that most of the electronic pH meters you might come across come with two core components. One of them is represented by the meter and the other consists of one or two probes that you need to place into the solution you want to test.
The electrode or electrodes that the model you’ve bought comes with are like mini chemical sets. They are in charge of measuring the pH, so they are by far the most important components in your device. That is why you should always make sure you treat them with care and clean them properly following every use. Do not scrub or rub them. Just wipe them clean.
How does a pH meter work?
For those prospective buyers and pH meter users who have nothing in common with chemistry, this explanation might seem a bit daunting. The fact is that most electrodes have potassium chloride inside them, which contains a number of hydrogen ions. The electrode, in other words, is responsible for measuring the number of hydrogen ions in the solution you are testing.
A glass electrode that a pH meter has been fitted with contains potassium chloride, and the pH of this substance is 7, so neutral. Basically, the electrode measures the difference between its own pH and that of the solution you are testing.
How to make accurate pH measurements
To ensure that the results you will read on your pH meter device are accurate, you first have to calibrate it properly. You can do so by dipping the electrodes into buffers, which are basically test solutions whose pH you know already. Then, you can adjust the device depending on the reading you are getting.
To some extent, pH measurements are temperature-dependent. Some even boast built-in thermometers which enable them to correct their measurements depending on the temperature of the environment where you’re utilizing the device. These products are far more accurate than those that do not come with thermometers.
Of course, if you are aware of the precise temperature of the liquid you want to find out the pH of, you can calibrate the device depending on those figures. Nevertheless, as is the case with anything else that involves a certain human touch, you need to be aware of the fact that you might not calibrate it correctly. That’s why we suggest you compare pH meters with built-in thermometers when you set out to find the best one your money can buy.
Even pH strips might be more or less accurate depending on who has manufactured them, so you need to understand that some errors might show up when you use any type of pH meters. Besides, getting a real device instead of a set of strips does offer two notable benefits.
One of them involves colorblind operators, which cannot understand and interpret the readings from pH strips. The other advantage is that a pH meter can be used time and again while strips are disposable. Even though they’re pretty affordable, you will still have to buy them over and over again if you do choose to use strips instead of an electronic alternative.
