The quality of household water is directly related to the physical health of each person. How to judge the quality of home water is also the best skill to master. Their own testing, although can not be compared with professional testing institutions, but also has a certain significance. To do this, it is important to first understand which indicators in the water can help us to get a rough estimate of the quality of water in our homes. Next, billion fan to introduce to you.
TDS value
TDS is the total dissolved solids, which indicates how many milligrams of dissolved solids are dissolved in 1 liter of water. The higher the TDS value, the more impurities the water contains. The impurities usually refer to the concentration of Ca2+, Mg2+, Na+ and K+ plasma in the water, and cannot directly indicate the quality of the water.
When we test the TDS of water, first open the TDS probe cover and press the button marked with the switch. After the LCD display, insert the TDS pen into the water under test. After the value is stable, press the HOLD button marked with the lower mark and take out the TDS pen to read the value.
Ordinary tap water measured between 260 and 600, if the number is more than 600, it is contaminated water.
Purity of water
Water is also pure, often measured by its salt content and resistivity, so we use an electrolyzer to measure the purity of water.
Put the two sets of iron and aluminum rods of the electrolyzer into two containers with water, the water level is close to the root of the iron and aluminum rods, then plug in the power supply, and finally press the switch. Electrolysis time is 15-60 seconds, be careful not to burn out the circuit. The amount of impurities in the water is then analyzed according to the color change of the water. Clean the iron bar in time after electrolysis.
After electrolysis, if the water is black, it contains heavy metals; If it is white, the water contains lead, zinc and other substances. If it is red, the water contains one valent mercury, three valent iron; If they are blue, they contain bacteria, viruses, etc. If the water is green, it means the water contains arsenic and other substances; If it is yellow, it means the water contains organic minerals such as dissolved oxygen.
But water is not the more pure the better, the human body still needs some minerals, long-term drinking pure water, due to the poor concentration of the reason, will take away the existing minerals and trace elements in the body, resulting in the loss of calcium and trace elements.
Residual chlorine content
Tap water is disinfected with chlorine in the waterworks, and residual chlorine refers to the effective chlorine left in the water after the water has been chlorinated and disinfected for a certain time.
You can use the purchased residual chlorine reagent and drop it into the prepared water for testing. Generally take 10ml tap water, drop 1-2 drops of residual chlorine reagent into the water, rest for about 10 minutes, the more yellow the water becomes, indicating the higher the residual chlorine content in the water.
The pH of water
If you want to test the pH of water, you need to drop 1-2 drops of purple litmus solution into 10ml water, shake evenly and watch the color. The redder the acid, the more purple the alkaline.
At present, acidic water is good or alkaline water is good at present there is no conclusion, often drink one of the harmful to people’s body, do not have to be too strong in fact alkaline water or acidic water, as long as the pH is not too much.
Mineral content
You can use the mineral detection pen to test the mineral content in the water. Press the switch button first, put it into the water to the water level, and judge the mineral content in the water according to the light of the green light.
It is worth noting that a mineral detection pen is divided into high grade and low grade. During the detection, the button should be moved to low grade first, and the number on the left side of the detection pen should be read out after being placed in water. A red light indicates that the mineral content in the water exceeds 40ppm, and you should turn the button to high and read the number on the right.
The mineral content value in tap water is generally 70-200, and the regulation cannot exceed 450. If it exceeds this range, it indicates that the mineral content in water is too high, which is not good for the body, but also easy to lead to life problems such as kettle scaling.