Physical and chemical testing and analysis in daily life
In a world full of mystery and infinite possibilities, the silver element attracts attention for its unique properties and wide range of uses. It is an antibacterial and anti-inflammatory medicine, a bright star of decorations, an important component of electronic products, and an indispensable part of human civilization. Well, in this article, we will delve into the wonderful world of the silver element, learn about its properties, discover its uses, and reveal the true value of this common yet often overlooked element in our daily lives. Let's embark on this wonderful journey of silver and appreciate the magic and charm of nature.
The discovery of silver can be traced back to 5,000 years ago, but it is impossible to determine who first discovered sterling silver. What we can be sure, however, is that silver has been considered a precious metal throughout history and has been used in the minting of coins, ornaments, and utensils.
In China, the discovery and use of silver dates back to the Spring and Autumn period, when archaeologists found silver filaments embedded in the surface of the utensils from bronzes. In the tombs of the Warring States and Han dynasties, many burial items such as silver collars, silver utensils and silver needles were unearthed. This shows that silver was already widely used in ancient China for decoration and crafts.
In the West, silver has also been regarded as a precious metal. During the ancient Greek and Roman empires, silver coins were widely issued and used in Western Asia and the Mediterranean, and had a profound influence on the numismatic system of later generations.
With the development of science, people's understanding of silver has also deepened. Chemically, silver is classified as element 47 and is located in the 11th subgroup of the periodic table. Its chemical symbol, AG, comes from the Latin word argentum, which also means "light, bright", and reflects the extremely high light reflectivity of silver.
Mankind's understanding of silver has gone through a long process from its discovery and use to scientific research. Today, silver plays an irreplaceable role not only in scientific, technological and industrial fields such as carbide cutting tools, rails for high-speed railways, aerospace and nuclear power generation, but also in jewelry making, tableware and water purification. At the same time, with the advancement of science and technology, people are also constantly exploring more environmentally friendly and efficient ways to extract and use silver.
Silver element applications.
1.Jewelry and Jewelry Manufacturing: Silver is widely used in the manufacture of jewelry, jewelry, rings, necklaces, etc., due to its beautiful appearance and oxidation resistance.
2.Coins and Investments: Silver is also used to mint coins and investment bars of silver. Silver investment is a common way to invest.
3.Electronics and electrical applications: Silver is an excellent conductive material, so it is used in the manufacture of wires, connectors, electrodes, batteries, and electronic components. Silver paste is also used in printed circuit boards.
4.Photography: In traditional photography, silver salts are used in photosensitive materials such as negatives and paper.
5.Medical applications: Silver has antimicrobial properties, so it is used in the preparation of antimicrobial medical supplies such as antimicrobial dressings, surgical instruments, and antimicrobial drugs.
6.Industrial uses: Silver is used in industry to make mirrors, catalysts, silver oxide batteries, and catalysts in other chemical reactions.
7.Food and beverages: Silver foil is commonly used in food and beverages, such as chocolate packaging and liquor labels in drinking wine.
8.Energy applications: Silver is used in solar cells to improve cell efficiency and as a heat conductive material in nuclear and thermoelectric power generation.
9.Decorative arts: Silver can be used to make decorative arts such as sculptures, paintings, and ornaments.
10.Preparation of chemical reagents: Silver nitrate and other silver compounds are used as chemical reagents in laboratories.
Silver is a versatile material that is widely used in different fields, and its unique properties such as electrical conductivity, antimicrobial, and beautiful appearance make it an essential part of various applications.
Physical properties of the silver element.
1.Appearance: Silver is an element with a bright silvery-white metallic luster, so it was also called "**" in ancient times
2.Density: Silver has a relatively high density of 105 grams of cubic centimeters. This means that it is relatively heavy and has a certain mass.
3.Melting Point: Silver has a relatively high melting point, which is about 96178 degrees Celsius (1763.)2 degrees Fahrenheit). This makes silver solid at room temperature.
4.Electrical Conductivity: Silver is an excellent conductive material with extremely high electrical conductivity, the highest of all metals. For this reason, silver is often used in wires, cables, electrodes, and other electronic components.
5.Thermal conductivity: Silver also has excellent thermal conductivity and is one of the best among metals. This makes silver very useful in the manufacture of thermally conductive materials and heat sinks.
6.Hardness: Sterling silver is relatively soft, but it can be doped or alloyed to increase its hardness. The hardness can be adjusted as needed to suit different applications.
7.Coefficient of expansion: Silver's coefficient of linear expansion is moderate, making it less prone to deformation or fracture when temperature changes.
8.Optical properties: Silver has good reflective properties for light, especially in the visible spectrum. As a result, silver is commonly used in the manufacture of mirrors, mirrors, and optical instruments.
9.Magnetism: Silver is a non-magnetic material, i.e., it does not show significant magnetism.
Silver is a metal with excellent electrical, thermal, and reflective properties, so it has a wide range of applications in electronics, electricians, optics, jewelry, industry, and many other fields. Its physical properties make it an important part of numerous industrial and scientific applications.
Elemental silver chemistry
Reactivity: Silver has high reactivity at room temperature and reacts with oxygen, water, acid and other substances. For example, silver reacts with oxygen to produce black silver oxide. When exposed to air, silver gradually oxidizes and forms a black oxide surface.
Acid reaction: Silver can react with nitric acid, hydrochloric acid and other acids to produce corresponding silver salts. For example, silver reacts with nitric acid to produce less soluble silver nitrate.
Redox: Silver can be in different oxidation states, most commonly +1 and +2 valence. Silver is usually present in elemental form, but compounds in different oxidation states can also be formed.
Alloy formation: Silver is often alloyed with other metals. The most common example is silver coins or silverware formed by silver and copper, which have good mechanical properties and corrosion resistance.
Complex formation: Silver can form stable complexes with other substances. These complexes can be used to catalyze reactions, as drugs, dyes, or other applications.
Silver has a white luster, is malleable, malleable, and resistant to most acids and oxidants. It has high reactivity in chemical reactions, and reacts with chlorine, bromine, nitric acid, etc., to form corresponding salts.
Elemental silver biological properties
Silver (Ag) has some specific biological properties in biology, and although it is not an essential element for life, it still has some importance in some biological systems. Here's a closer look at the biology of silver:
1.Antimicrobial: Silver exhibits significant antimicrobial and antimicrobial properties. Silver ions (AG+) have inhibitory or killing effects on a variety of microorganisms, including bacteria, fungi and viruses. As a result, silver is widely used in the preparation of antimicrobial medical supplies, such as antimicrobial dressings, surgical instruments, and antimicrobial drugs.
2.Antioxidant properties: Silver has some antioxidant properties, which can help protect cells and biomolecules from oxidative damage. This property plays a role in cell protection and resistance to oxidative stress.
3.Toxicity: Although silver is antimicrobial to microorganisms, at high concentrations, silver is also toxic to humans and other organisms. Long-term or overexposure to silver can trigger silver poisoning, leading to a range of health problems such as inflammation, eye problems, and breathing problems.
4.Excretion and metabolism: Silver usually enters living organisms in its ionic form (AG+). In living organisms, the way silver is metabolized and excreted varies depending on the individual and environmental conditions. Silver can be excreted in the body through urine, feces, and sweat.
5.Bioenrichment: Certain biological systems, such as some aquatic plants and microorganisms, can enrich for silver ions. This phenomenon of bioaccumulation has certain applications in environmental monitoring and remediation.
6.Environmental impacts: The release of large quantities of silver into the environment, especially due to industrial wastewater and waste, can have a negative impact on aquatic life and soil ecosystems. Therefore, it is important to monitor and control silver concentrations in the environment.
Silver has antimicrobial and antioxidant properties in biological systems, but can be toxic at high concentrations. Therefore, the biological properties of silver need to be carefully considered in medical, antimicrobial applications, and environmental monitoring. In addition, the role of silver in biological systems is still being studied**.
The element silver is distributed in nature
Silver is relatively less distributed in nature and is usually found in the form of ores. Here's a closer look at the distribution of silver in nature:
1.Mineral distribution: Silver is mainly in the form of ores, common silver ores include pyrite (AG2S), silver sulfide ore (AG2S2), silver chloride ore (AGCL), etc. These minerals are often found in conjunction with other metallic minerals such as lead, zinc, copper, etc.
2.Mineral distribution: Global silver minerals are mainly located in a number of regions, with some of the major silver mining countries including Mexico, Peru, China, Russia and Australia. The geology of these areas makes for an abundance of silver minerals.
3.Form distribution: Silver occurs in nature in many forms, including free metal forms, alloy forms, and compound forms. In some ores, silver is found in elemental form, but more commonly in the form of compounds.
4.Types of Silver Deposits: Silver deposits are generally classified as hydrothermal type, alkali leaching type, and sedimentary type. Hydrothermal silver deposits are the most common type and form in a high-temperature, high-pressure environment deep in the earth's crust. Alkali leaching silver deposits are formed in an alkaline environment, while sedimentary silver deposits are formed in a seafloor sedimentary environment.
5.Reserves: The total global silver reserves are relatively limited, and it is estimated that the global silver reserves are around 11About 650,000 tons. This makes the relative abundance of silver in the metal lower.
Silver exists in the form of ore in nature, mainly distributed in some areas with special geological conditions. Global silver resources are relatively limited, so their mining and utilization require careful consideration to ensure sustainability and environmental friendliness.
Silver mining and smelting
The mining and smelting of silver is a multi-step process that includes mining, ore processing, extraction of silver, refining, and production of silver products. The following is a detailed introduction to the process of mining and smelting the element silver:
1.Mining: Silver ore is usually located underground, and the depth of the deposit varies from region to region. Mining begins in search of silver deposits. Once found, mining is carried out, usually through underground or open pit mining. Underground mining involves digging tunnels, roadways, and shafts to obtain ore. Open-pit mining involves removing soil and rock from the surface and then extracting the ore.
2.Ore Processing: After mining, the ore needs to be crushed, ground and beneficiated. These processes help to separate the useful ore from the waste ore and prepare it for further smelting.
3.Smelting: The smelting process of silver usually involves the following steps:
a.Ore smelting: The silver in the ore is melted, often along with other metals, to form a coarse silver alloy. This is usually done in a high-temperature furnace.
b.Crude silver separation: Crude silver alloys contain impurities that need to be separated by different smelting and refining methods. Among them, the electrolysis method and the fire method of silver are common methods.
Electrolysis: A crude silver alloy is placed in an electrolytic cell to separate the silver from other metals by means of an electric current. It is a highly effective method and is commonly used in the production of high-purity silver.
Fire method: Through the fire method, a crude silver alloy is heated to a high temperature so that the other metals oxidize and evaporate or burn out, while the silver remains at the bottom. This includes processes such as the displacement, loosening, and sublimation of gold.
4.Refining: The resulting silver after smelting often also contains some impurities that require further refining to improve purity. The refining process typically includes chemical treatments such as redox, dissolution, recrystallization, and electrolysis.
5.Silver production: Refined silver can be used to produce a variety of silver products, such as coins, jewelry, tableware, etc. These products need to be machined and cast.
Environmental and health safety issues need to be considered throughout the process to ensure that the smelting and manufacturing process has the least impact on workers and the environment. In addition, the modern smelting process also employs advanced technologies to improve efficiency and reduce energy consumption.
Commonly used detection methods for silver element
Atomic Absorption Spectrometry (AAS): This is a commonly used method of measuring the content of metal elements. The amount of silver is determined based on the intensity of the absorbed light by converting the silver atoms in the sample into a gaseous state and then using a light source of a specific wavelength for absorption measurements.
Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES): This is a highly sensitive and selective measurement method. The amount of silver is determined by converting the silver atoms in the sample into charged ions and excitation at high temperatures to emit light of a specific wavelength, and then measuring the intensity of the light.
X-ray fluorescence spectroscopy (XRF): This is a non-destructive measurement method. By irradiating a sample with X-rays, the silver atoms in the sample are excited and emit fluorescence of a specific energy, using the intensity of the fluorescence to determine the amount of silver.
Capillary electrophoresis (CE): This is an analytical method based on electrodynamic effects. By migrating the silver ions in the sample with some charged solvent, the amount of silver is measured based on the rate and time of migration.
Let's take atomic absorption as an example to introduce this technology. First of all, we need to understand the principle of atomic absorption. Atomic absorption is a quantitative analysis method based on atomic energy level transitions, which determines the amount of light radiation in a particular element by measuring the degree to which that element's atoms absorb that element.
In the measurement of silver, atomic absorption method has high accuracy and sensitivity, which provides an effective means to study the chemical properties, compound composition and content of silver.
Next, we use atomic absorption to measure the amount of silver. The specific steps are as follows:
Prepare the sample to be tested. The silver sample to be measured is prepared into a solution, which is generally digested with mixed acids to facilitate subsequent measurements.
Choose the right atomic absorption spectrometer. Depending on the nature of the sample to be measured and the range of silver content to be measured, the appropriate atomic absorption spectrometer is selected.
Adjust the parameters of the atomic absorption spectrometer. According to the element to be measured and the instrument model, adjust the parameters of the atomic absorption spectrometer, including the light source, atomizer, detector, etc.
Measure the absorbance of the element silver. The sample to be measured is placed in an atomizer and a specific wavelength of optical radiation is emitted through the light source, and the element to be measured, silver, absorbs this light radiation, creating an energy level transition. The absorbance of silver is measured by a detector.
5.Calculate the amount of elemental silver. Based on the absorbance and standard curve, the amount of silver is calculated. The following are the specific parameters used by a device to measure silver.
Silver (AG).
Standards: Sterling silver wire, silver powder (99.)99) or silver nitrate (9999％）。
Method:: Weigh 0 accurately1000g of silver powder, dissolved in 10ml (1 1) nitric acid, with a level to determine the volume to 100ml, the concentration of ag in this solution is 1000 g ml. Store in a polyethylene bottle protected from light.
Flame type: Air acetylene, lean flame.
Analyze the parameters
Wavelength (nm) 3281
Spectral bandwidth (nm) 04
Filter factor 03
Recommended lamp current (mA) 2
Negative high pressure (V) 2725
Burner head height (mm) 6
Integration time(s) 3
Air pressure and flow rate (mpa,) 024
Acetylene pressure and flow rate (mpa,) 005, linear range (g ml) 001～1.50
Characteristic concentration (g ml) 0018
Limit of Detection (g ml) 0003
rsd(%)0.2035
Calculation method: Continuous method.
Solution acidity 05％ hno3
Testing**
Calibration curves:
Interference
Air No interference was found in the acetylene flame. The presence of a small amount of chlorine causes the formation of AGCL precipitate, so the solution is preferably nitric acid medium, and the water used for analysis and preparation of reagents should be ion exchange water.
In practice, it is necessary to select the appropriate measurement method according to the specific needs of the site. These methods are widely used in laboratories and industry for the analysis and detection of silver.
Silver, this mysterious element, has won endless praise and admiration from mankind for its unique charm and wide application. From ancient currency minting, ornament making, to modern industrial applications, silver has always played an important role in human society.
However, the mining and use of silver also poses a number of environmental and social concerns. Therefore, we need to take a deeper understanding of silver in order to better leverage its benefits while reducing its potential negative effects. Scientists are constantly working to find new methods and technologies to extract and use silver in a more environmentally friendly and efficient way.
Silver is a magical and important element. It is not only a key driving force for the development of modern science and technology, but also an important resource for our sustainable development in the future. Let us look forward to silver playing a greater role in the fields of science, technology and industry in the future, and making greater contributions to the progress of human society. At the same time, we should also pay more attention to the environmental and social impacts of silver mining and use, so as to achieve sustainable development and harmonious coexistence between man and nature.