Ice. Ice Paronims - Ice ice on the water as it is called
About -1.8 ° C.
Assessment of quantity (density) sea ice Given in points - from 0 ( pure water) Up to 10 (solid ice).
Properties
The most important properties of sea ice are porosity and saline that determine its density (from 0.85 to 0.94 g / cm³). Because of the low density of ice, the ice floes rise above the surface of the water at 1/7 - 1/1 of their thickness. The melting of sea ice begins at temperatures above -2.3 ° C. Compared with freshwater, it is more difficult to learn about the parts and more elastic.
Salinity
Density
Sea ice is a complex physical body consisting of crystals fresh ice, brine, air bubbles and various impurities. The ratio of the components depends on the conditions of gland formation and subsequent ice processes and affects the average ice density. Thus, the presence of air bubbles (porosity) significantly reduces the density of the ice. The salty of ice has a smaller impact on the density than porosity. With ice salting 2 ppm and zero porosity, ice density is 922 kilograms on a cubic meter, and with porosity 6 percent decreases to 867. At the same time, at zero porosity, the increase in saline from 2 to 6 ppm leads to an increase in ice density only from 922 to 928 kilograms on a cubic meter.
Thermophysical properties
Shades of sea ice in large arrays vary from white to brown.
White Loda It is formed from snow and has many air bubbles or cells with brine.
The young marine ice line of a grainy structure with a significant amount of air and brine often has green color.
Perennial peasic ice, of which impurities are extruded, and young ice, which freezed in calm conditions, often have blue or blue color. Blue also happens Glether Loda and Icebergs. In blue ice, the needy structure of crystals is clearly visible.
Brown Or the yellowish ice has a river or coastal genesis, there are impurities of clay or humic acids.
The initial types of ice (ice fat, shuga) have dark grey Color, sometimes with a steel tint. With an increase in ice thickness, its color becomes lighter, gradually moving into white. When melting, thin ice cream becomes gray again.
In case the ice contains a large amount of mineral or organic impurities (plankton, eologic suspension, bacteria), its color may vary on red, Pink, Yellow, up to black.
Due to the property of ice, delay long-wave radiation, it is able to create a greenhouse effect, which leads to the heating of water under it.
Mechanical properties
Under the mechanical properties of ice understand its ability to resist deformations.
Typical types of ice deformation: stretching, compression, shift, bending. Three stages of ice deformation are distinguished: elastic, elastic-plastic, destruction stage. Accounting for the mechanical properties of ice is important when determining the optimal course of icebreakers, as well as when placed on the ice floes, polar stations, when calculating the strength of the vessel case.
Conditions of education
In the formation of sea ice between the entirely fresh crystals of the ice, small drops of salt water are turned out, which gradually flow down. The freezing temperature and the temperature of the greatest seawater density depends on its saline. Sea water, the saltness of which is lower than 24,695 ppm (the so-called saltwater water), when cooled, first reaches the greatest density, like fresh water, and with further cooling and the absence of stirring quickly reaches the freezing temperature. If the saltness of the water is higher than 24,695 ppm (salty water), it is cooled to the freezing temperature with a constant increase in the density with continuous stirring (exchange between the upper cold and lower warm layers of water), which does not create conditions for the rapid heating and freezing of water, that is, Salted oceanic water freezes the same weather conditions.
Classifications
Sea ice in his own way location and mobility divided into three types:
- floating (drifting) ice,
In ice development stages Several so-called initial types of ice (in order of education):
- intravel (including bottom or anchor), formed at some depth and in water in water under conditions of turbulent stirring of water.
Further education of ice types - nilasovy ice:
- nilas, formed with a calm surface of the sea from a sludge and snow bears (Dark Nilas to 5 cm thick, light Nilas to 10 cm thick) - thin elastic ice crust, easily flexing on water or zybi and generating gear layers for compression;
- the flasks formed in the collapsed water with a calm sea (mainly in the bays, near the mouth of the rivers) - a fragile shiny crust of ice, which is easily breaking under the action of waves and wind;
- the pancake ice, formed with a weak excitement from an ice salary, snow, or shugs or due to faults as a result of the glance of the flask, Nilas or the so-called young ice. It is an ice plate of a rounded form from 30 cm to 3 m in diameter and a thickness of 10-15 cm with raised edges due to wiping and shocks of the ice.
Further Ice Education Development Stages are young icewhich are divided into gray (thickness 10-15 cm) and gray-white (thickness of 15-30 cm) ice.
Sea ice, developing from young ice and having age no more than one winter period, is called annual ice. This annual ice can be:
- thin annual ice - white led 30-70 cm thick,
- middle thickness - 70-120 cm,
- thick annual ice - more than 120 cm thick.
If the sea ice is melting at least for one year, he belongs to old ice. Old ice are divided into:
- residual annual - who did not celebrate the summer of the ice, which is again in the frozenning stage,
- two-year-old - existed for more than one year (the thickness reaches 2 m),
- perennial - old ice thick 3 m and more, who has survived melting at least two years. The surface of such ice is covered with numerous irregularities, hormones formed as a result of repeated melting. Lower surface perennial ice Also distinguished by large irregularities and variety of form.
Thickness of perennial ice in
The ratios between ice crystals under various conditions of formation: 1 - a prismatic ice crystal (the formation occurs at high height with severe frosts), 2 - Scheduled ice (formed during severe frosts), s - cupid ice (formed in wet caves), 4 - ordinary snowflake. By E.K. Lazarenko, 1971
Properties
Loda Besmevetnin. In large clusters, it acquires a bluish shade. Glitter glass. Transparent. Spoundism has no. Hardness 1.5. Fragile. Optically positive, the refractive index is very low (n \u003d 1.310, nm \u003d 1.309).
Formation form
In nature, the ice is a very common mineral. In the earth's crust there are several types of ice: river, lazy, marine, soil, fond and gutter. More often, it forms aggregate accumulations of small crystalline grains. Also known crystalline ice formations arising with a sublimation path, that is, directly from the vapor state. In these cases, the ice has the appearance of skeletal crystals (snowflakes) and skeletal and dendritic growth units (cave ice, hoarflash, frost and patterns on glass). Large well-cut crystals are found, but very rare. N. N. Zhulov describes the ice crystals of the northeastern part of Russia, met at a depth of 55-60 m. From the surface with an isometric and columnal appearance, the length of the largest crystal was 60 cm., And the diameter of its base is 15 cm. From ordinary Forms on ice crystals Revealed only the verge of hexagonal prism (1120), hexagonal biimid (1121) and Pinacoid (0001).
Ice stalactites, called the surprises of "icicles", are familiar to everyone. When temperatures drops around 0 ° in the autumn-winter seasons, they grow everywhere on the surface of the earth with slow freezing (crystallization) flowing and dripping water. They are also common in ice caves.
Icy breaking They are strips of ice cover from ice crystallizing on the border of water-air along the edges of the reservoirs and the bordering edges of the puddle, the banks of rivers, lakes, ponds, reservoirs, and TP. With non-freezing the rest of the water space. When they are complete, solid ice cover is formed on the surface of the reservoir.
Lode also forms parallel-sixth aggregates in the form of fibrous veins in porous soils, and on their surface - ice antolithi.
Education and field
The ice is formed mainly in water basins with a decrease in air temperature. At the same time, an ice porridge appears on the water surface, isolated from ice needles. Long ice crystals are increasing from below, in which the axis of the sixth order symmetry is placed perpendicular to the surface of the crust. The ratios between ice crystals under different conditions of formation are shown in Fig. The ice is spread throughout where there is moisture and where the temperature drops below 0 ° C. In some areas, the ground ice is thawing only on a slight depth, below which the eternal permafrost begins. These are the so-called regions of permafrost; In the areas of distribution of many-nesting rocks in the upper layers of the earth's crust, the so-meas are found. underground ice
, among which the modern and fossil underground ice distinguish. At least 10% of the entire land sushi area covers glaciers, the consideration of their monolithic ice rock is called ice Loda. The iceplay is formed mainly from the accumulation of snow as a result of its sealing and transformation. Ice Pokrov takes about 75% of Greenland Square and almost all Antarctica; The greatest capacity of glaciers (4330 m.) - installed near the station Bard (Antarctica). In Central Greenland, the thickness of ice reaches 3200 m.
Ice deposits are well known. Locally with cold long winter and short summerAlso, in high mountainous areas, ice caves with stalactites and stalagmites are formed, among whom Kungurskaya in the Perm region of the Slovakia is the most interesting, as well as the Cave of Doboshin in Slovakia.
As a result of the freezing of sea water formed sea Loda. The characteristic properties of sea ice are saline and porosity, which determine the range of its density from 0.85 to 0.94 g / cm 3. Because of such a small density, the ice floes rise above the water surface by 1/7-1 / 10 of its thickness. Sea ice begins to melt at temperatures above -2.3 ° C; It is more elastic and more difficult to crush into parts than a freshwater led.
Practical value
Lode is mainly used in refrigeration, as well as for various purposes in medicine, everyday life and technology.
Loda (eng. ICE) - H. 2 O.
CLASSIFICATION
| Strunz (8th edition) | 4 / A.01-10 |
|---|---|
| Dana (8th edition) | 4.1.2.1 |
| Hey "S CIM REF. | 7.1.1 |
Physical properties
| Mineral color | colorless passed on white, pale blue passed in greenish blue in thick layers |
|---|---|
| Color trash | white |
| Transparency | transparent, translucent |
| Shine | glass |
| Hardness (Moos scale) | 1.5 |
| Frame | sink |
| Strength | fragile |
| Density (measured) | 0.9167 g / cm3 |
| Radioactivity (GRAPI) | 0 |
| Magitan | Diamagnetic |
Optical properties
| A type | union |
|---|---|
| Refractive indices | nα \u003d 1.320 Nβ \u003d 1.330 |
| Maximum birefringence | Δ \u003d 1.320 |
| Optical relief | moderate |
Info-lesson on the topic Ice Paronyms - Ice
Info-lesson plan:
1. The installation of paronyms ice - ice
2. Examples of phrases with a paronym ice
3. Examples of proposals with a paronym ice
4. Examples of phrases with a paronym ice
5. Examples of proposals with a paronym ice
1. The depreciation of the Ice Paronims - Ice
Ice - 1) located on ice;
2) Torked in ice.
ICE - 1) of ice covered with ice;
2) very cold (cold as ice);
3) (over.) Extremely discreet, contemptuous-cold, destroying.
2. Examples of phrases with a paronym - ice
1) Ice Mainland
2) Ice Palace
3) Ice Stadium
4) Ice Airport
5) ice hike
6) ice road
7) ice trail
8) Ice
9) Ice field
10) Ice Expedition
11) Ice Bare
12) Ice fun
13) Ice Mode
14) Ice obstacle
15) Ice congestion
16) Ice Barrier
17) Ice cam
18) Ice Cross
3. Examples of proposals with a paronym - Ice
1) water temperature Barents Sea At different depths during the year are inconsistent, since the amount of warm waters, bringing by the Nordsk region. Depending on the season, it happens different. It affects ice Sea mode.
2) when meeting with ice The icebreaker "captures" the nasal part on the edge of the ice and swallows it.
3) Exploring Antarctic, captain Nemo falls into ice captivity.
4) the first heroes of the Soviet Union were the Soviet pilots who saved the Expedition of the Paarozhin "Chelyuskin" who fell into ice captivity.
5) up to 4 km in height above sea level ice Shield Antarctica.
6) "Life Road" - ice
8) work ice Roads, "Roads of Life", made it difficult to enemy aviation.
9) Communication with Leningrad was maintained only by air and through Ladoga lakein which winter was laid ice The route is the legendary "way of life."
10) In the center of Russia, along the mighty River Yenisei, there is a Siberian land - the region, which is called Taiga, although he is mountain, and the tundra, and the arctic, and ice.
11)Ice Drift lasted for 4 months.
12) The people say: November - Laptop, semi-displacement, ice blacksmith.
13) classes are held in the gym and on ice Playground.
14)Ice The mode plays a big role in the life of Lake Baikal.
15)Ice The river mode is very complex.
16) even in Antarctica people who explore ice Pokrov, relief and climate of the mainland.
17) In 1821, Faddey Faddeevich Bellinshausen, together with Mikhail Petrovich Lazarev penetrated ice Barrier surrounding the South Pole.
18) Glacier - ice Cap on the tops of the mountains.
19) in the northern part of the Atlantic, where the lively sea routes are running, is constantly on the Watch Special ice patrol.
20) Bobsley - sport, which is a high-speed descent from the mountains on a specially equipped ice Runs on managed sleigh - beans.
21) In the summer of 1956, within the framework of the third international geophysical year, a high-tech Arctic expedition for the study of the strait between Greenlandia and Spitsbergen forces of scientists of the USSR, Sweden and Norway was carried out. The program of work provided for the landing of an international group of scientists on ice The dome of Northern Schitsberegin, and to fulfill this task was the Mi-4 helicopter, which was commanded by the test pilot R.I. Kaprelyan.
22)Ice Baikal shell keeps from 4.5 to 6 months.
23) ice hockey - sports team game on ice
24) in winter, where acts ice Crossing, put signs about the permissible load on this road.
25) In 1242, at the sunrise, the famous battle of the lake on the ice of the lake was called Ice Weight.
4. Examples of phrases with a paronym - ice
1) ice zone
2) ice continent
3) ice vertices
4) Icelb
5) Ice Mountain
6) Ice Coast
7) Ice Route
8) ice wave
9) ice cover
10) ice edge
11) Ice World
12) ice cave
13) ice wind
14) Ice frost
15) ice water
16) Ice rain
17) ice cereals
18) Ice crumb
19) ice icicle
20) Icy Crystal
21) Ice Cork
22) Ice ball
23) Ice Rod
24) ice tone
25) ice look
26) Ice reception
27) Icy fingers
5. Examples of proposals with a paronym - ice
1) Antarctica - ice mainland.
2) B. ice The cover of Antarctica contains about 80% of all freshwater of the Earth and 90% of all natural ice Planets.
3) fish splashing in ice water.
4)Icy The surface of the pond was covered since the beginning of winter a thick layer of snow.
5) The boy on the sledes went down with ice Gorki.
6) Caught ice water of the mighty ocean. Dead White Desertes Look Abreare icy Fields with frozen ice boulders. They are called torosa. (N.I.Selakov. From north to south ...)
7) from the north blowing ice wind.
8) The face is covered at one point ice Cork, and icicles grow on the eyebrows and beard.
9) He headed around this gigantic icy Fields trying to find a passage of ice, and as a result I completely cut this ice array.
10) Kungurskaya icy Cave is a unique monument of nature.
11) Kungurskaya icy The cave was formed on the site of the Great Permian Sea 10 - 12 thousand years ago.
12)Icy The surface of Eastern Antarctica is smoother and high (up to 4000 meters).
13) if the main difficulty in learning the relief icy Dome are climatic conditionsSupporting geodesic works and flights with aerial photography, then to study a treated relief, you need to learn to still see through the ice. This can only geophysics. Therefore, she owns the basic word about the structure of Antarctica.
14) from small icy Crystal in the clouds are formed snowflakes.
15) The Arctic is divided into two zones: icy The zone and zone of the Arctic desert.
16)Icy Zone is the sea of \u200b\u200bthe Arctic Ocean along with the islands.
17) on the Islands of the Arctic is located icy zone.
18) South ice Zones along the shores nordic seas The tundra zone stretches.
19) Fuck - one of the types of ice on Lake Baikal. It is formed in the initial phase of the freezing of the lake in the form of fine ice Edges - tackle, or in the fall from the splas of the waves on the rocks and stones.
20) Snowflake is ice Crystal with hex symmetry.
21) Snow is precipitation in the form icy crystals.
22) Fluffy icy Moram coated branches.
23) Gerd managed to melt icy Heart of kay.
24) hanging behind the cooler ice,
He is full of droplets and smells in the spring. (Icicle)
25) High sheer cliffs icy The shores are an insurmountable barrier.
27) B. ice The cover of Antarctica is incurred 80% of the entire fresh water of the planet. The surface of the mainland icy The shield is covered with stratum snow.
28) in March-April 2002 from icy Antarctician's shield was separated by iceberg more than 70 km long, which is highly rare and is considered as one of the evidence of modern climate warming.
29) And who visited there [in Antarctica] once, he will always remember the great silence ice The desert painted in the morning clock in gentle radiance, lilac and pink beds beds, cold rims and polar lights, cozy lights of wintering, covered by snow drifts. (By A.M.Gusev)
30) How can I use fresh water that is contained in glaciers? The project of transporting icebergs to countries with a arid climate began to be developed back in the 20th century. To solve this problem, several ways were offered. One of them is the grinding of iceberg in place, loading formed ice Crumbs in tankers and further transportation to the destination. The advantage of this method is that in this case it does not have to worry about the melting - the resulting water will be reliably splashing in the tanker. A clear minus is high cost.
31) Winter is a wonderful time of year. Her icy Beauty enchants and raises admiration.
32) swimming lovers in winter in ice Water is called walrus.
33) B. ice
34)Ice
35) On the last day of the carnival women, celebrating the ending of the spinning, rode ice The mountains on the dongings of the splash, and it was believed that the farther they would pass, the longer the flax.
36)Ice Pokrov makes a heavy life of underwater inhabitants.
37) Polar Bear inhabit icy Opens and islands of the polar pool south to northern coasts Siberia and North America.
38) In what fairy tale the evil queen took the boy into his ice palace?
39) The polar bear is often referred to as a tireless skeleton of the Arctic. Most often it can be seen slowly craving among endless snow fields or icy Toros. This huge beast is iron muscles. It is covered by a thick layer of fat and a white or a little golden skin with a thick wool. Even the soles of the paws are protected by fur. The beast is able to float in ice Open ocean water cover the distance to tens of kilometers.
40) needle - ice House of indigenous inhabitants of the northern part of North America.
6.Tests
1)ice wind
2)icy expedition
3)icy frost
4)icy water
In one of the phrases below, the selected word is incorrectly used. Find the error and correct it. Write the phrase number and the correct word.
1)ice hike
2)icy icicle
3)ice crystal
4)icy crust
In one of the phrases below, the selected word is incorrectly used. Find the error and correct it. Write the phrase number and the correct word.
1)ice rain
2)icy Crup
3)icy chit
4)Icy Boying
In one of the phrases below, the selected word is incorrectly used. Find the error and correct it. Write the phrase number and the correct word.
1)ice Salt
2)ice crossing
3)ice sight
4)ice mainland
1) ice hockey - sports team game on ice Playground with washer and keys.
2) swimming lovers in winter in ice Water is called walrus.
3) B. ice The zone grow lichens, mosses, polar poppies.
4)Ice The wind swears above his head.
In one of the proposals below, the selected word is incorrectly used. Find the error and correct it. Write a guest number and the correct word.
1) Snow is precipitation in the form icy crystals.
2) Fluffy icy Moram coated branches.
3) "Road of Life" - icy Road through Ladoga in winter 1941-1943.
4) Gerd managed to melt icy Heart of kay.
7.Things
|
Test Quest Number |
Phone or Offer | |
|
ice |
Located aggregate state, which is peculiar to have a gaseous or liquid form at room temperature. Ice properties began to study hundreds of years ago. About two hundred years ago, scientists discovered that water is not a simple compound, but a complex chemical element consisting of oxygen and hydrogen. After opening the formula, the water began to have a view H 2 O.
The structure of ice
H 2 o consists of two hydrogen atoms and one oxygen atom. In calm condition, hydrogen is located on the vertices of the oxygen atom. Oxygen and hydrogen ions should occupy the vertices of an equifiable triangle: oxygen is located on the vertex of the direct angle. This building is called the dipole.
The ice consists of 11.2% of the percent of hydrogen, and the rest is oxygen. Ice properties depend on its chemical structure. Sometimes there are gaseous or mechanical formations - impurities.
The ice is found in nature in the form of a few crystalline species that stably retain their structure at temperatures from zero and lower, but at zero and above it begins to melt.
Structure of crystals
The properties of ice, snow and steam are completely different and depend on in solid state H 2 O is surrounded by four molecules located in the tetrahedron corners. Since the coordination number is low, the ice can have an openwork structure. This is displayed on the properties of ice and its density.
Ice shapes
The ice refers to common substances in nature. On Earth there are the following varieties:
- river;
- lake;
- nautical;
- fond;
- gULTER;
- soil.
There are ice, directly formed by sublimation, i.e. From a vapor state. This species takes the skeleton form (we call them snowflakes) and aggregates of dendritic and skeletal growth (frost, frost).
One of the most common forms are stalactites, i.e. icicles. They grow worldwide: on the surface of the earth, in the caves. This type of ice is formed by flowing the water drops when the temperature difference is about zero degrees in the autumn-spring period.
Education in the form of ice strips appearing along the edges of the reservoirs, on the boundary of water and air, as well as the edge of the puddle, are called icy pancakes.
The ice can be formed in porous soils in the form of fibrous veins.
Ice properties
The substance may be in different states. Based on this, the question arises: and what property is manifested in a particular state?
Scientists allocate physical and mechanical properties. Each of them has its own characteristics.
Physical properties
The physical properties of ice include:
- Density. In physics, the non-uniform medium is represented by the limit of the mass of the substance of the medium itself to the volume in which it is concluded. The density of water, as well as other substances, is a function of temperature and pressure. Typically, a constant water density is used in the calculations equal to 1000 kg / m 3. A more accurate density indicator is taken into account only when it is necessary to accurately calculate the importance of the resulting density difference.
When calculating the density of ice is taken into account, what water has become ice: as it is known, the density of salt water is higher than distilled. - Water temperature. Usually occurs at zero degrees. Freezing processes occur jumps with heat release. The reverse process (melting) occurs when absorbing the same amount of heat that was allocated, but without jumps, and gradually.
In nature, there are conditions under which water is undercooling, but it does not freeze. Some rivers retain the liquid water condition even at a temperature of -2 degrees. - The amount of heat that is absorbed when heating the body for each degree. There is a specific heat capacity, which is characterized by the amount of heat required for heating a kilogram of distilled water per degree.
- Compressibility. Another physical property of snow and ice is compressibility that affects the decrease in the volume under the influence of increased external pressure. The inverse value is called elasticity.
- Ice strength.
- Ice color. This property depends on the absorption of light and dispersion of the rays, as well as on the number of impurities in frozen water. The river and lake ice without extraneous impurities are visible in the gentle blue light. Sea ice can be completely different: blue, green, blue, white, brown, having a steel shade. Sometimes you can see the black ice. Such a color it acquires due to large number Minerals and various organic impurities.
Mechanical properties of ice
The mechanical properties of ice and water are determined by the impact of the external environment relative to the unit area. Mechanical properties depend on the structure, salinity, temperature and porosity.
The ice is an elastic, viscous, plastic formation, but there are conditions under which it becomes solid and very fragile.
Sea ice and freshwater vary: the first is much plastic and less durable.
During the passage of ships, the mechanical properties of ice are required. It is also important when using ice roads, crossing and not only.
Water, snow and ice have similar properties that determine the characteristics of the substance. But at the same time, many other factors affect these readings: temperature ambient, impurities in solid, as well as the original composition of the liquid. Ice is one of the most interesting substances on Earth.
, cal / g
0.51 (0 ° C)
79,69
677
Greatly decreases with a decrease in temperature
Thermal expansion coefficient, 1 / ° C
9.1 · 10. -5 (0 ° C)
Thermal conductivity,cal /( see seconds·· ° C)
4.99 · 10. -3
Refractive index:
For ordinary ray
For extraordinary ray
1.309 (-3 ° C)
1,3104 (-3 ° C)
Specific electrical conductivityoh. -1 ·cm -1
10 -9 (0 ° C)
Apparent activation energy 11kcal / Mole
Surface electrical conductivity,oh. -1
10 -10 (-11 ° C)
Apparent activation energy 32kcal / Mole
Jung module,dIN / SM.
9 · 10. 10 (-5 ° C)
Polycristalich. ice
Resistance,MN / M. 2 :
Crushing
Razm
Cut
2,5
1,11
0,57
Polycrystalline Loda
Polycrystalline Loda
Polycrystalline Loda
Average effective viscositypZ.
10 14
Polycrystalline Loda
The degree of power flow
Activation energy during deformation and mechanical relaxation,kcal / Mole
11,44-21,3
Linearly growing 0.0361kcal /( mole· ° C) from 0 to 273.16 to
Note. 1 Cal / (g× ° С) \u003d 4,186kJL( kg(TO); 1 oh. -1 × cm -1 =100 sim / m; 1 dIN / SM.=10 -3 n / m; 1 cal /( cm( sec× ° С) \u003d 418.68w /( m.(TO); 1 pZ \u003d.10 -1 N.( sec / m 2 .
Table. 2. - Quantity, distribution and lifetime of ice 1
| Square distribution | Medium concentrate | Massigation rate, g / year | Average lifetime, year |
||||
| Underground Loda | |||||||
| Sea Loda | |||||||
| Snow cover | |||||||
| Icebergs | |||||||
| Atmospheric Loda | |||||||
Due to the widespread water and ice on ground surface The sharp difference of part of the properties of ice from the properties of other substances plays an important role in natural processes. Due to less than in water, the density of the ice forms floating cover on the surface of water, protecting rivers and reservoirs from freezing to the bottom. The relationship between the steady flow rate and the voltage in polycrystalline ice is hyperbolic; With an approximate description of its power equation, the inclination of the extent increases as the voltage grows; In addition, the flow rate is directly proportional to the activation energy and inversely proportional to the absolute temperature, so that with a decrease in the temperature of the ice approaches an absolutely solid body. On average, the temperature of ice fluctuate is close to melting 10 is 10 times higher than that of rocks. Thanks to the fluidity of the ice, it does not accumulate it impossible, and flows from those parts of the earth's surface, where it falls more than it becomes (see glaciers). Due to the very high reflectivity of ice (0.45) and especially snow (up to 0.95), the area covered with them - on average, about 72 million km 2 in high and medium latitudes of both hemispheres - receives solar heat by 65% \u200b\u200bless than the norm and is a powerful source of cooling of the earth's surface than a largely due to modern latitudinal climatic zonality. In the summer in the polar regions, solar radiation is larger than in the equatorial belt, however the temperature remains low, because a significant part of the heat absorbed is spent on melting ice having a very high heat of melting.
II, III and V I II, III and V are preserved at atmospheric pressure if the temperature does not exceed -170 ° C. When heated approximately to -150 ° C, they turn into a cubic ice (ice IC), not shown in the diagram, since it is unknown whether it is a stable phase. Dr. The method of obtaining ice IC is the condensation of water vapor to the cooled to -120 ° C. When condensation of vapors on a colder substrate, amorphous ice is formed. Both of these ice molds can spontaneously switch to hexagonal ice, and the sooner the higher the temperature.
Lod IV is a metastable phase in the ice stability zone V. Llead IV is easier formed, and possibly stable if heavy water is exposed to the pressure. The melting curve of the ice VII was examined to pressure 20 Gn / m 2 (200 thousand kgf / cm 2). At the same time, the pressure of the LED VII melts at a temperature of 400 ° C. Lod VIII is a low-temperature ordered form of ice VII. IX IX is a metastable phase that occurs when I III III and is essentially a low-temperature form. In general, the phenomena of supercooling and metastable equilibrium are very characteristic of the phases formed by water. Some of the metastable equilibrium lines are indicated on the diagram dotted line.
Fig. 2. The scheme of the ice structure I (the oxygen atoms and the directions of hydrogen bonds are shown) in two projections.
