Jumayeva Nilufar lead!

Jumayeva Nilufar
LEAD!
Lead is one of the oldest known metals. It is one of the most common elements used over the centuries. It blocks toxic radiation. It has been used in sanitary installations and pipes for years. It is a widely used and easily processed material in nature. Lead is one of the elements of the carbon group, which is used in many products in the chemical industry, medicine and the automotive industry. May cause poisoning due to toxic properties. Because of its toxicity, a form called "lead confetti" has been used as a liquid weapon. It is one of the rare metals that blocks radiation.
Chemical symbol Pb
The Latin name is Plumbum
Atomic number 82
Period 4
Relative atomic mass 207.2
Group 4.A
Oxidation rate 0, 2, 4
Electronic configuration 4f14 5d10 6s2 6p2
Aggregation Status Solid
CAS number 7439-92-1
Opened in 1751
Ionization energy [eV] 7.41
Electromagnetism 2.33
Density 11.34 g / cm³
Lead is a chemical element belonging to group IV of the R-Mendeleev periodic table, atomic mass 207.2. Natural lead has 5 stable isotopes: 2 (, 2R (very small amounts), 2MR (1.5%), 206R (23.6%), 2 (| 7R (22.6%)) and 208R (52.3%).
Lead was found in Egypt, Mesopotamia, and elsewhere between 6,000 and 7,000 BC. known to the peoples of the rest of the world. They made statues, household utensils and other items from lead. The Romans used lead as a water pipe. Greece and Qad. In Rome, Lead compounds - Lead ash RO and Lead white paint 2RSO, R (ON), were used to make various drugs and dyes.
The edges of the lead crystallize in the form of a centered cube. There is no allotropic deformation of lead; liquefaction temperature 327.4 °, boiling point 1725 °, density 11.34 g / cm3. The oxidation states of lead in its compounds are +2 and +4; is not a chemically active element. Lead oxides R20, RO, R02, R304 and R203 are known. In the absence of oxygen, water does not affect lead. The R (ON) and R (ON) 4 hydroxides of Q are amphoteric. the hydrogen compound RN4 is a colorless gas, an unstable substance that decomposes into R and N2. When lead is heated together with halogens, it forms RX2-containing, water-soluble halides (where X is a halogen).
In industry, lead is obtained from R8 and partly from oxygenated compounds of lead. Metal case q. In order to obtain it, R8 is burned in the presence of air, and the formed RO is returned to the rough Q. under the influence of coal. Lime is added to restore the R8YU3 formed during the firing process. The sketch Q contains 92-98% R, the rest is Si, A§ (sometimes Ai), 2p, 8p, A $, V1, Ge.
A large amount of lead q. spent on battery-wires. Due to the absorption of lead and other radioactive rays, lead is used to make containers for radioactive substances and X-ray equipment. Power cables are coated with lead to protect them from corrosion and mechanical impact. Many alloys are formed on the basis of lead. Lead oxide is used in the manufacture of RO crystals and optical glass. Its azide and stifiate (trinitroresorcinate) are used as incendiaries for explosives. Lead tetraethyl is an antidote. To determine the presence of N28, see. acetate is used. The stable isotope of lead is 204R and the radioactive isotope is 2 | 2R. Lead drugs are used to treat skin diseases.
Plants get the lead they need from soil, water, and atmospheric precipitation. The human body contains 0.22 mg of lead per day through food, 0.1 mg through water and 0.08 mg of lead through dust. The amount of lead should not exceed 0.2-2 mg per day. Excess lead poisons the body. As a result, the liver, cardiovascular system, lungs and other organs become infected. In the treatment of such patients, special (complex-forming) and general healing drugs (glucose, various vitamins) and physiotherapy are used. Prevention is important in the prevention of lead infections. For this purpose, the use of other metals (eg, zinc) instead of lead, the use of titanium white paint instead of lead white paint, automation and mechanization of lead production, ventilation of workplaces, personal protection of workers, periodic medical examinations. important.
Questions on mastering the topic:
1. From what compounds is lead obtained?
a) Taken from cast iron and steel
b) Taken from lead ash
c) Obtained from oxygenated compounds
2. Atomic mass?
a) 402,1
b) 109,6
c) 207,2
3. Sequence number?
a) 78
b) 91
c) 82
4. Melting point?
a)237,5C
b)243,5C
c) 327,5C
5. How many stable isotopes does lead contain?
a)9
b)4
c)5


Thank you for your attention!