Can potassium K be dated?

It's a deep question. I had to check the information carefully.

It is well known that element C is often used as a geological, archaeological, paleontological and other dating measurement because its C14 has a stable half-life.

While the K element has three isotopes of K39, K40, K41, of which only K40 is radioactive, and has a certain abundance and stable half-life, so salt mines can be surveyed by detecting its radioactivity.

Reference: "How to Find Potash Salt" - Compiled by the 16th Geological Team of Yunnan Provincial Geological Bureau, 1978

In geological survey, potassium-argon dating is a commonly used method, that is, the technology of using the principle of decay of potassium-40 in minerals into argon 40. It dates more than 100,000 years and is one of the radioactive dating techniques commonly used in paleoanthropology. It is mainly used for the determination of the age of igneous rocks in geology.

The half-life of Potassium-40 is about 1.3 billion years, and archaeological applications are mainly to determine early Paleolithic sites and ancient human dating. The absolute age of hominin or site can be determined using the potassium-argon method because the fossils or sites are buried in volcanic ash, or the strata of the site are associated with volcanic rock layers and can be compared. In the past 30 years, due to the development and application of dating methods, it has provided an absolute dating basis for the history of human development since the fourth century, and laid a relatively reliable foundation for the establishment of a world chronological system since the late Paleolithic and Neolithic periods.

Reference: Practical Encyclopedia of Secondary School Teaching Politics Volume - Sha Fumin et al., eds., 1994

ps: These two books are too old, just if you want to popularize science, it is still "potassium argon method generation" or"Potassium argon dating"bar.

The flame reaction mentioned upstairs is a method for measuring the content of K elements, (there are slight differences in the flame color of different concentrations of K content), and there should be a more accurate measurement method, but this is not within the scope of my knowledge.

Yes, using the flame color reaction. Through the blue co-glass, the flame is purplish-red.

The detection of potassium ions is by flame color reaction, and there is no ion equation.

Potassium ions can give the flame a purple color, which can be detected by the flame color reaction and a flame photometer.

Potassium (K+) and sodium (Na+).

When examined by the flame color reaction, their flames are light purple (through a blue cobalt glass sheet) and yellow, respectively.

Na+ can react with uranyl zinc acetate to form a yellowish sodium uranyl zinc acetate precipitate, which is commonly used to test sodium ions in solution.

No, potassium ions are tested by a flame reaction (blue-violet through blue cobalt glass).

K+, Na+, Ca2+, Mg2+, HCO3-, NO3-, Cl-, SO42-, these 8 kinds are the 8 major ions commonly found in water.

Brief introduction of each ion:

K+: The potassium ion is an ion obtained by the loss of one of the outermost electrons of the potassium atom, which is positive 1 valence and is written as k+. Potassium ions can also be obtained by dissolving or melting potassium salts. The potassium ion reaches a stable structure of 8 electrons outside the nucleus.

Na+: The sodium ion is obtained by the sodium atom losing one of the outermost electrons, and it is written as Na+. Sodium is a soft, light, waxy, and very malleable silvery-white group 1a alkali metal element.

Ca2+: Calcium ion is an indispensable ion for various physiological activities of the body. It is essential for maintaining biopotentials on both sides of cell membranes and maintaining normal nerve conduction function.

Normal muscle contraction and diastolic function, neuromuscular conduction function, and some hormonal mechanisms are expressed through calcium ions.

Mg2+: Magnesium ions are obtained by the loss of the outermost two electrons of the magnesium atom and are written as mg+.

HCO3-: The atomic arrangement of bicarbonate (HCO3-) is a planar structure, with carbon in the center, bonded to three oxygen atoms (one C=O, one C-Oh, and one C-O-). It is a conjugate base of carbonic acid and a conjugate acid of carbonate ions.

There is the following equilibrium in the aqueous solution, bicarbonate can be ionized to form carbonate ions (CO32-) and hydrogen ions (H+), and hydroxide ions (OH-) and carbonic acid (H2CO3), because the degree of hydrolysis (production of OH-) of bicarbonate is greater than that of ionization (production of H+), so its aqueous solution is weakly alkaline.

NO3-: nitrate refers to the anion of nitrate, chemical formula: NO, nitrate is -1 valence, where N is the most ** + 5 valence.

Cl-: Chloride ion (Cl-) is a -1 valence ion of chlorine that is widely present in nature and is colorless. Chloride ions are the most abundant anions in living organisms and participate in a variety of biological functions through transmembrane transport and ion channels.

SO42-: Sulfate, a compound composed of sulfate ions (SO42-) and other metal ions, is an electrolyte, and most of them are soluble in water. Sulfate minerals are salts formed by the phase combination of metal element cations (including ammonium) and sulfates.

Since sulfur is a variable valence element, it can form different minerals in different valence states in nature. When it is combined with four O2- in the highest valence state S6+ to form SO42-, it is then combined with the metal element cation to form sulfate. Among the sulfate minerals, there are more than 20 kinds of metal cations combined with sulfate.

That is, salts containing sulfates are sulfates.

It refers to the eight ions with the most content in water, namely calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), and internal carbonic acid capacity.

Root (CO32-), bicarbonate (HCO3-), sulfate (SO42-) and chloride ion (Cl-).

Extended Materials. Ion refers to a stable structure in which an atom loses or gains one or several electrons due to its own or external action, bringing it to the outermost shell with an electron count of 8 or 2 (helium atoms) or no electrons (four neutrons). This process is called ionization. The energy required or emitted by the ionization process is called ionization energy.

In a chemical reaction, the metallic element atom loses its outermost electron, and the non-metallic atom gains electrons, thus giving the atom or cluster of atoms participating in the reaction an electric charge. Charged atoms are called ions, positively charged atoms are called cations, and negatively charged atoms are called anions. Anions and cations form uncharged compounds due to electrostatic action.

Like molecules and atoms, ions are the basic particles that make up matter. For example, sodium chloride is composed of chloride ions and sodium ions.

It refers to the eight ions with the largest content of bai in water, and du is calcium (Ca2+).

Magnesium zhi (Mg2+), sodium (Na+), potassium (

DAOK+), carbonate (CO32-), bicarbonate (HCO3-), sulfate (SO42-) and chloride (Cl-).

Eight major ions bai

It mainly refers to the eight major lizhi with the largest du content in water

molecules, i.e., calcium ions (Ca2+), magnesium ions (inner Mg2+), sodium ions (Na+), potassium ions (K+), carbonate ions (CO32-), bicarbonate ions (HCO3-), sulfate ions (SO42-) and chloride ions (Cl-).

Four anions: carbonate ion, CO32, sulfate ion, SO42, bicarbonate ion, HCO3, chloride ion, Cl

Four cations: sodium na calcium ca2 potassium k magnesium mg2

The eight ions mainly refer to the eight ions with the most abundant content in water, namely calcium ions (daoca2+).

Magnesium ion (Mg2+), sodium ion (Na+), potassium ion (K+), carbonate ion (CO32-), bicarbonate ion (HCO3-), sulfate ion (SO42-) and chloride ion (Cl-).

Four anions: carbonate ion, CO32, sulfate ion, SO42, bicarbonate ion, HCO3, chloride ion, Cl

Four cations: sodium na calcium ca2 potassium k magnesium mg2

Inorganic, both potassium and sodium salts are soluble in water and do not precipitate. These two ions can be tested only by a flame reaction. Sodium ions are yellow, potassium ions are light purple (through blue cobalt glass).

Sodium precipitation of zinc uranyl acetate (only encountered in college).

Potassium K+ Calcium Ca2+ Na+ Magnesium Mg2+ Aluminum Al3+

Zinc Ion Zn2+ Iron Ion Fe3+ Ferrous Ion Fe2+ Hydrogen Ion H+ Copper Ion Cu2+

Hg2+ Ag + Barium Ba2+ O2 O2- Cl-

Sulfate ions SO42- hydroxide oh-chlorate CLO3- nitrate NO3- carbonate CO32-

Ammonium NH4+ (Note: all plus and minus signs should be written on the top right).

Each other is a common ion formed after an atom loses electrons, consisting of sodium ions and magnesium ions.

It's okay hahahahaha.

Inward rectification is not an inward current, inward rectification is the direction of current change, not the direction of the current itself, for example, the increase of outward current is outward rectification, and the decrease of outward current is inward rectification.

Inward rectification refers to the phenomenon that the ion channel closes with the depolarization of the cell membrane, in the resting state, the potassium ion channel is opened, and the electrochemical driving force of potassium ions is balanced with the membrane potential, due to the existence of reverse transport such as sodium-potassium pumps, potassium ions make the cell membrane at resting potential through outflow, but in the process of depolarization, because the potassium ion channel is gradually blocked, it is closed, and the phenomenon of inward rectification occurs.

Because the IK1 channel is more permeable to the K inflow during superpolarization than the K outflow during depolarization, it is called the inward rectified K channel. In essence, depolarization mediates K efflux (the outflow of K through IK1 is close to 0 at the time of membrane depolarization to 20 mV or corrected) in the penultimate natural paragraph of page P87 of the physiology book. IK1 mediates both K influx and K efflux.

I want to say that all the answers under the question are not very accurate, in fact, the potassium ion inward integration current ik1 is the potassium ion outflow gradually decreases at the end of the 3rd period, and becomes the influx in the 4th period, that is to say, from the end of the 3rd period to the 4th period, the inward integration current is the transition of potassium ions from the gradual decrease of the outflow to the gradual increase of the inflow My statement is absolutely reliable, if you don't believe it, you can go to the figure on page 202 of the 8th edition of the 2nd edition of Pharmacology published by Renwei.

Ion channels normally pass in both directions, and rectification means that the channel is selective in the direction of the current, in the process of myocardial action potential repolarization phase 2, that is, the plateau phase. One of the most important reasons for the formation of the plateau period is the inward rectification characteristic of IK1, which is very permeable at resting potential, and mainly outward current. When the membrane is hyperpolarized and the negative value of the membrane potential is greater than the equilibrium potential of IK1, the electric field force that promotes the influx of potassium ions is greater than the concentration potential energy that promotes the outflow of potassium ions, so the influx of potassium ions occurs, and the permeability is high. Conversely, when the membrane is depolarized, the permeability of IK1 decreases, and the outflow of potassium ions through IK1 decreases, and the outflow of potassium ions through IK1 is close to zero when the depolarization is lower or positive.

Obviously, this channel has greater permeability to the influx of potassium ions during hyperpolarization than the outflow of potassium ions during depolarization, like the action of a diode. This phenomenon in which the permeability of potassium ions is reduced by depolarization of the membrane is called inward rectification. In the outward rectifier potassium channel, the outflow current of potassium ions is much greater than that of potassium inflow under the same voltage difference.

More than -40mV I think introversion means that the curve of the voltage-current graph is curved downwards and the direction of the ion current should not be directly related (although the direction of the current is indeed inward at the time).

The phenomenon that the permeability of the IK1 channel to K+ is reduced due to the depolarization of the membrane is called inward rectification.

I would like to ask, the eighth edition of the physiology book says that the inward rectifier potassium channel begins to work in the second plateau stage, and the potassium ions in the super-membrane state should be inflow, so why is it still the main outward current in the second phase?