The chemical symbol for Bromine is Br. Zirconium is a chemical element with atomic number 40 which means there are 40 protons and 40 electrons in the atomic structure. As the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine. The chemical symbol for Palladium is Pd. The entire structure then consists of this unit cell repeating in three dimensions, as illustrated in Figure 10.46. Change the volume units to cm. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation) stabilizes the free metal somewhat against further oxidation. As shown in Figure 10.48, a solid with this type of arrangement consists of planes (or layers) in which each atom contacts only the four nearest neighbors in its layer; one atom directly above it in the layer above; and one atom directly below it in the layer below. citation tool such as, Authors: Paul Flowers, Klaus Theopold, Richard Langley, William R. Robinson, PhD. Consequently, stable structures for ionic compounds result (1) when ions of one charge are surrounded by as many ions as possible of the opposite charge and (2) when the cations and anions are in contact with each other. ni Temperature 1x1010 cm-3 300 K (room temp.) These electrons together weigh only a fraction (let say 0.05%) of entire atom. The density of a substance strongly depends on its atomic mass and also on the atomic number density. The information contained in this website is for general information purposes only. Fermium is a chemical element with atomic number 100 which means there are 100 protons and 100 electrons in the atomic structure. In diamond atom, there are atoms in the eight corners and six atoms in the center of each face of cube. This structure is also called cubic closest packing (CCP). Francium is an alkali metal, that has one valence electron. Use Wien's law calculator to find the temperature of any hot object based on its thermal emission spectrum. The atomic radius of a chemical element is a measure of the distance out to which the electron cloud extends from the nucleus. Wiki User. Calculate the areal density of atoms (# of atoms/cm 2) on (110) plane. The chemical symbol for Actinium is Ac. Structures are determined by two principal factors: the relative sizes of the ions and the ratio of the numbers of positive and negative ions in the compound. Xenon is a chemical element with atomic number 54 which means there are 54 protons and 54 electrons in the atomic structure. How to use this density mass volume calculator. An X-ray diffractometer, such as the one illustrated in Figure 10.65, may be used to measure the angles at which X-rays are diffracted when interacting with a crystal as described earlier. Barium is a chemical element with atomic number 56 which means there are 56 protons and 56 electrons in the atomic structure. Silicon dioxide (which is also known as silicates) is a monosaccharide made up of one hydrogen atom with two electrons. In some respects zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. This effect is caused by a decrease in the atomic number density. Holmium is a chemical element with atomic number 67 which means there are 67 protons and 67 electrons in the atomic structure. Answers and Replies Oct 13, 2009 . Tellurium is a chemical element with atomic number 52 which means there are 52 protons and 52 electrons in the atomic structure. The chemical symbol for Mendelevium is Md. c) 1.67 x 10^24 electrons. Technetium is a chemical element with atomic number 43 which means there are 43 protons and 43 electrons in the atomic structure. This is illustrated by an alternate description of the CsCl structure in which the lattice points are located in the centers of the cesium ions. Neodymium is a chemical element with atomic number 60 which means there are 60 protons and 60 electrons in the atomic structure. The chemical symbol for Radium is Ra. Although neodymium is classed as a rare earth, it is a fairly common element. Tellurium is far more common in the universe as a whole than on Earth. The chemical symbol for Gold is Au. $(b)$ Repeat part (a) for $2 \times 10^{15}$ boron atoms per $\mathrm{cm}^{3}$ added to silicon. The equation is density = mass/volume. Scandium is a chemical element with atomic number 21 which means there are 21 protons and 21 electrons in the atomic structure. Gadolinium belongs to a rare earth elements (it is one of a set of seventeen chemical elements in the periodic table). This variation is typically small for solids and liquids but much greater for gases. Neodymium is a soft silvery metal that tarnishes in air. The three most common basic crystal patterns are: This website was founded as a non-profit project, build entirely by a group of nuclear engineers. When metal atoms are arranged with spheres in one layer directly above or below spheres in another layer, the lattice structure is called simple cubic. The chemical symbol for Zirconium is Zr. Mercury is a chemical element with atomic number 80 which means there are 80 protons and 80 electrons in the atomic structure. Chlorine is a yellow-green gas at room temperature. Want to cite, share, or modify this book? ), Therefore, the density of Po=3.4711022g3.791023cm3=9.16 g/cm3Po=3.4711022g3.791023cm3=9.16 g/cm3. (b) Determine the density of alpha polonium. At.Wt. Thallium is a chemical element with atomic number 81 which means there are 81 protons and 81 electrons in the atomic structure. By rotating our perspective, we can see that a CCP structure has a unit cell with a face containing an atom from layer A at one corner, atoms from layer B across a diagonal (at two corners and in the middle of the face), and an atom from layer C at the remaining corner. The chemical symbol for Lutetium is Lu. Platinum is one of the least reactive metals. If Ni was simple cubic, its density would be given by: Yttrium is a chemical element with atomic number 39 which means there are 39 protons and 39 electrons in the atomic structure. Some of the properties of metals in general, such as their malleability and ductility, are largely due to having identical atoms arranged in a regular pattern. Protactinium is a chemical element with atomic number 91 which means there are 91 protons and 91 electrons in the atomic structure. The density of a material varies with temperature and pressure. Uranium is a chemical element with atomic number 92 which means there are 92 protons and 92 electrons in the atomic structure. Atoms in BCC arrangements are much more efficiently packed than in a simple cubic structure, occupying about 68% of the total volume. The Face-Centered Cubic (FCC) unit cell can be imagined as a cube with an atom on each corner, and an atom on each face. Neon is a chemical element with atomic number 10 which means there are 10 protons and 10 electrons in the atomic structure. Uranium has the highest atomic weight of the primordially occurring elements. Iodine is the least abundant of the stable halogens, being the sixty-first most abundant element. 100% (4 ratings) for this solution. b. The unit cell consists of lattice points that represent the locations of atoms or ions. For now, we will focus on the three cubic unit cells: simple cubic (which we have already seen), body-centered cubic unit cell, and face-centered cubic unit cellall of which are illustrated in Figure 10.50. Copper is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. The distance between the center of the silicon number density of silicon atoms is 4.99 10 cm, the mass density is 2.33 g/cm. This arrangement is called a face-centered cubic (FCC) solid. Iodine is a chemical element with atomic number 53 which means there are 53 protons and 53 electrons in the atomic structure. Sodium is a soft, silvery-white, highly reactive metal. In this arrangement, each atom touches 12 near neighbors, and therefore has a coordination number of 12. Plutonium is a chemical element with atomic number 94 which means there are 94 protons and 94 electrons in the atomic structure. Argon is mostly used as an inert shielding gas in welding and other high-temperature industrial processes where ordinarily unreactive substances become reactive; for example, an argon atmosphere is used in graphite electric furnaces to prevent the graphite from burning. The first alloy used on a large scale was bronze, made of tin and copper, from as early as 3000 BC. Selenium is a nonmetal with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. (a) In a diffractometer, a beam of X-rays strikes a crystalline material, producing (b) an X-ray diffraction pattern that can be analyzed to determine the crystal structure. These condensers use tubes that are usually made of stainless steel, copper alloys, or titanium depending on several selection criteria (such as thermal conductivity or corrosion resistance). The smaller of the holes is found between three anions in one plane and one anion in an adjacent plane. The chemical symbol for Chlorine is Cl. Cerium is the second element in the lanthanide series. Caesium has physical and chemical properties similar to those of rubidium and potassium. Density of Silicon is 2.33g/cm3. What is the distance (center-to-center) between nearest Ga and As atoms? The chemical symbol for Terbium is Tb. The cubic form of zinc sulfide, zinc blende, also crystallizes in an FCC unit cell, as illustrated in Figure 10.61. The larger type of hole is found at the center of six anions (three in one layer and three in an adjacent layer) located at the corners of an octahedron; this is called an octahedral hole. What is the approximate diameter of a silicon atom (length of a bond) in a solid block of th; The intrinsic carrier concentration of single crystal silicon is (1.5 times 10^{10}) per cubic centimeter. The structure of a crystalline solid, whether a metal or not, is best described by considering its simplest repeating unit, which is referred to as its unit cell. The chemical symbol for Promethium is Pm. Titanium is a lustrous transition metal with a silver color, low density, and high strength. nearest#Ga#atoms#is#the#same#as#the#distance#between#nearest#As#atoms.# # # 3) Silicon#(Si)#has#a#diamond#crystal#structure.##Answer#the#following# . Depending on the relative sizes of the cations and anions, the cations of an ionic compound may occupy tetrahedral or octahedral holes, as illustrated in Figure 10.58. From such measurements, the Bragg equation may be used to compute distances between atoms as demonstrated in the following example exercise. Being a typical member of the lanthanide series, europium usually assumes the oxidation state +3. Lawrencium is a chemical element with atomic number 103 which means there are 103 protons and 103 electrons in the atomic structure. Silicon is a diamond like structure. Actinium is a chemical element with atomic number 89 which means there are 89 protons and 89 electrons in the atomic structure. calculating the cube root of Max' atoms per cm and sqaring the result should give us the wanted atoms per cm. Neodymium is not found naturally in metallic form or unmixed with other lanthanides, and it is usually refined for general use. Atomic mass of Silicon is 28.0855 u. The most commonly used spontaneous fission neutron source is the radioactive isotope californium-252. The chemical symbol for Phosphorus is P. As an element, phosphorus exists in two major formswhite phosphorus and red phosphorusbut because it is highly reactive, phosphorus is never found as a free element on Earth. The chemical symbol for Holmium is Ho. And since each simple cubic unit cell has one atom at each of its eight corners, there is 818=1818=1 atom within one simple cubic unit cell. There are seven different lattice systems and 14 different unit cells. 3) of silicon . The chemical symbol for Americium is Am. The volume of an atomis about15 orders of magnitudelargerthan the volume of a nucleus. Lead is a heavy metal that is denser than most common materials. Rhenium is a chemical element with atomic number 75 which means there are 75 protons and 75 electrons in the atomic structure. Iridium is a chemical element with atomic number 77 which means there are 77 protons and 77 electrons in the atomic structure. The chemical symbol for Thallium is Tl. It is also sometimes considered the first element of the 6th-period transition metals and is traditionally counted among the rare earth elements. Silicon has an atomic weight of 28.09 and a lattice constant equal to 5.43 A. The figure on the left depicts waves diffracted at the Bragg angle, resulting in constructive interference, while that on the right shows diffraction and a different angle that does not satisfy the Bragg condition, resulting in destructive interference. Dysprosium is a chemical element with atomic number 66 which means there are 66 protons and 66 electrons in the atomic structure. Hafnium is a lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in many zirconium minerals. Note: The length unit angstrom, , is often used to represent atomic-scale dimensions and is equivalent to 1010 m. Drawing a right triangle on the face of the unit cell, we see that the length of the diagonal is equal to four chloride radii (one radius from each corner chloride and one diameterwhich equals two radiifrom the chloride ion in the center of the face), so d = 4r. The chemical symbol for Chromium is Cr. The chemical symbol for Argon is Ar. Palladium is a chemical element with atomic number 46 which means there are 46 protons and 46 electrons in the atomic structure. It is a soft, silvery-white alkali metal. We can think of this as chloride ions forming an FCC cell, with sodium ions located in the octahedral holes in the middle of the cell edges and in the center of the cell. Europium is a chemical element with atomic number 63 which means there are 63 protons and 63 electrons in the atomic structure. Nickel is a silvery-white lustrous metal with a slight golden tinge. It is also the most corrosion-resistant metal, even at temperatures as high as 2000 C. Lead has the highest atomic number of any stable element and concludes three major decay chains of heavier elements. If we know the edge length of a unit cell of an ionic compound and the position of the ions in the cell, we can calculate ionic radii for the ions in the compound if we make assumptions about individual ionic shapes and contacts. Calculate the volume density of Si atoms (# of atoms/cm 3) given that lattice constant a = 5.43 A. What is Atomic Number Density - Definition, What is Radius and Density of Atomic Nucleus - Definition, What is Density Formula - Density Equation - Definition, What is Uranium in the Environment - Definition, What is Quark in the Standard Model - Definition, What is Electron in the Standard Model - Definition. Praseodymium is a soft, silvery, malleable and ductile metal, valued for its magnetic, electrical, chemical, and optical properties. Terbium is a silvery-white, rare earth metal that is malleable, ductile, and soft enough to be cut with a knife. Determine the density of silicon/ Homework Equations? Main purpose of this project is to help the public learn some interesting and important information about chemical elements, ionizing radiation, thermal engineering, reactor physics and nuclear energy. The chemical symbol for Nickel is Ni. Mass was no longer considered unchangeable in the closed system. It readily forms hard, stable carbides in alloys, and for this reason most of world production of the element (about 80%) is used in steel alloys, including high-strength alloys and superalloys. Lawrencium is the final member of the actinide series. Gold is a bright, slightly reddish yellow, dense, soft, malleable, and ductile metal. Oh, look! We can think of this as chloride ions forming a simple cubic unit cell, with a cesium ion in the center; or as cesium ions forming a unit cell with a chloride ion in the center; or as simple cubic unit cells formed by Cs+ ions overlapping unit cells formed by Cl ions. This book uses the It explains how we use cookies (and other locally stored data technologies), how third-party cookies are used on our Website, and how you can manage your cookie options. Calcium is an alkaline earth metal, it is a reactive pale yellow metal that forms a dark oxide-nitride layer when exposed to air. If the cations are too large to fit into the octahedral holes, the anions may adopt a more open structure, such as a simple cubic array. It is anintensive property, which is mathematically defined as mass divided by volume: In words, the density () of a substance is the total mass (m) of that substance divided by the total volume (V) occupied by that substance. TYU 1.3 (a) Determine the distance between nearest (100) planes in a simple cubic lattice with a lattice constant of a _ TYU 1.5 atoms Oxygen is a colourless, odourless reactive gas, the chemical element of atomic number 8 and the life-supporting component of the air. Since a Po unit cell contains one-eighth of a Po atom at each of its eight corners, a unit cell contains one Po atom. If you continue to use this site we will assume that you are happy with it. The chemical symbol for Oxygen is O. Because of its closed-shell electron configuration, its density and melting and boiling points differ significantly from those of most other lanthanides. Germanium is a chemical element with atomic number 32 which means there are 32 protons and 32 electrons in the atomic structure. Any atom in this structure touches four atoms in the layer above it and four atoms in the layer below it. The fact that FCC and CCP arrangements are equivalent may not be immediately obvious, but why they are actually the same structure is illustrated in Figure 10.53. Due to thequantum nature of electrons, the electrons are not point particles, they are smeared out over the whole atom. a) the distance from the center of one silicon atom to the center of its nearest neighbor, (b) the number density of silicon atoms (#/cm. When an ionic compound is composed of a 1:1 ratio of cations and anions that differ significantly in size, it typically crystallizes with an FCC unit cell, like that shown in Figure 10.60. They can be described by unit cells with either cations at the corners or anions at the corners. Rhodium is a rare, silvery-white, hard, corrosion resistant and chemically inert transition metal. The chemical symbol for Silver is Ag. and you must attribute OpenStax. Ionic compounds with similar-sized cations and anions, such as CsCl, usually form a simple cubic structure. It is a member of the chalcogen group on the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Molybdenum a silvery metal with a gray cast, has the sixth-highest melting point of any element. The chemical symbol for Iodine is I. Iodine is the heaviest of the stable halogens, it exists as a lustrous, purple-black metallic solid at standard conditions that sublimes readily to form a violet gas. After developing ovarian cancer, Franklin continued to work until her death in 1958 at age 37. Some metals crystallize in an arrangement that has a cubic unit cell with atoms at all of the corners and an atom in the center, as shown in Figure 10.51. The orientation of the four calcium ions about the fluoride ions differs. The chemical symbol for Dysprosium is Dy. Tungsten is a chemical element with atomic number 74 which means there are 74 protons and 74 electrons in the atomic structure. A freshly exposed surface of pure copper has a reddish-orange color. Silver is a soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. This dependence is usually expressed by thecoefficient of linear or volume expansion. Note that, each element may contain more isotopes, therefore this resulting atomic mass is calculated from naturally-occuring isotopes and their abundance. c) Based on your answer in Part B, how many electrons are in this amount of 13C? The chemical symbol for Iridium is Ir. A possible crystal structure of Silicon is face-centered diamond-cubic structure. The chemical symbol for Germanium is Ge. From the Pythagorean theorem, we have: The radius of the potassium ion is 1.33 . They were awarded the 1962 Nobel Prize in Physiology or Medicine, along with Maurice Wilkins, who provided experimental proof of DNAs structure. Boron is a chemical element with atomic number 5 which means there are 5 protons and 5 electrons in the atomic structure. The chemical symbol for Aluminum is Al. The chemical symbol for Potassium is K. Potassium was first isolated from potash, the ashes of plants, from which its name derives. V=l3=(3.524108cm)3=4.3761023cm3V=l3=(3.524108cm)3=4.3761023cm3 Under normal conditions, sulfur atoms form cyclic octatomic molecules with a chemical formula S8. A pure metal is a crystalline solid with metal atoms packed closely together in a repeating pattern. A face-centered Ca unit cell has one-eighth of an atom at each of the eight corners (818=1(818=1 atom) and one-half of an atom on each of the six faces 612=3612=3 atoms), for a total of four atoms in the unit cell. The chemical symbol for Lithium is Li. It is this repeated pattern which control properties like strength, ductility, density, conductivity (property of conducting or transmitting heat, electricity, etc. A crystal lattice is a repeating pattern of mathematical points that extends throughout space. The chemical symbol for Europium is Eu. Promethium is one of only two such elements that are followed in the periodic table by elements with stable forms. Gadolinium is a chemical element with atomic number 64 which means there are 64 protons and 64 electrons in the atomic structure. Like all elements with atomic number over 100, lawrencium can only be produced in particle accelerators by bombarding lighter elements with charged particles. There are 8 atoms in a unit cell of Si. There are two reasons for the difference between mass number and isotopic mass, known as themass defect: Note that, it was found therest mass of an atomic nucleusis measurably smaller thanthe sum of the rest masses of its constituentprotons,neutronsand electrons. The chemical symbol for Rhodium is Rh. a) 0.462 mol 13C. In metals, and in many other solids, the atoms are arranged in regular arrays called crystals. When an ionic compound is composed of cations and anions of similar size in a 1:1 ratio, it typically forms a simple cubic structure. The diffraction of X-rays scattered by the atoms within a crystal permits the determination of the distance between the atoms. The smaller cations commonly occupy one of two types of holes (or interstices) remaining between the anions. In a compound of carbon and oxygen, silicon is substituted for carbon with the same value of density as silicon dioxide. Vanadium is a chemical element with atomic number 23 which means there are 23 protons and 23 electrons in the atomic structure. To calculate the atomic concentration one needs to know two things: the lattice constant to calculate the volume of the unit cell and the number of atoms that can fit into the lattice. In nuclear industry boron is commonly used as a neutron absorber due to the high neutron cross-section of isotope 10B. The chemical symbol for Zinc is Zn. The density of silicon is 2.33 g/cm3 and the density of amorphous silicon dioxide is 2.27 g/cm . 3. In nuclear industry gadolinium is commonly used as a neutron absorber due to very high neutron absorbtion cross-section of two isotopes 155Gd and 157Gd. Nitrogen is a chemical element with atomic number 7 which means there are 7 protons and 7 electrons in the atomic structure. The chemical symbol for Fermium is Fm. There are two tetrahedral holes for each anion in either an HCP or CCP array of anions. Ex 1.3 density of atoms for a (a) (100) plane and (b) (110) plane. Ytterbium is a chemical element with atomic number 70 which means there are 70 protons and 70 electrons in the atomic structure. The atomic number density (N; atoms/cm 3), which is associated with atomic radii, is the number of atoms of a given type per unit volume (V; . Rhodium is a chemical element with atomic number 45 which means there are 45 protons and 45 electrons in the atomic structure. Silver is a chemical element with atomic number 47 which means there are 47 protons and 47 electrons in the atomic structure. Consequently, unit cell axes join points with identical environments. At 0.099%, phosphorus is the most abundant pnictogen in the Earths crust. The density of calcium can be found by determining the density of its unit cell: for example, the mass contained within a unit cell divided by the volume of the unit cell. It rarely occurs in its elemental state or as pure ore compounds in the Earths crust. Density of silicon atoms. Polonium is a chemical element with atomic number 84 which means there are 84 protons and 84 electrons in the atomic structure. Bromine is a chemical element with atomic number 35 which means there are 35 protons and 35 electrons in the atomic structure. The mention of names of specific companies or products does not imply any intention to infringe their proprietary rights. The volume of unit cell equals to . The atoms at the corners touch the atoms in the centers of the adjacent faces along the face diagonals of the cube. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. Half of the cubic holes are occupied in SrH2, UO2, SrCl2, and CaF2. (b) Density is given by density=massvolume.density=massvolume. OpenStax is part of Rice University, which is a 501(c)(3) nonprofit. A BCC unit cell contains two atoms: one-eighth of an atom at each of the eight corners (818=1(818=1 atom from the corners) plus one atom from the center. Thulium is a chemical element with atomic number 69 which means there are 69 protons and 69 electrons in the atomic structure. 5.07 g/cc. The chemical symbol for Erbium is Er. Radon is a radioactive, colorless, odorless, tasteless noble gas. British chemist Rosalind Franklin made invaluable contributions to this monumental achievement through her work in measuring X-ray diffraction images of DNA. Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. The OpenStax name, OpenStax logo, OpenStax book covers, OpenStax CNX name, and OpenStax CNX logo How to calculate volume with density and mass and other combinations. It is important to realize that values for ionic radii calculated from the edge lengths of unit cells depend on numerous assumptions, such as a perfect spherical shape for ions, which are approximations at best. Typical densities of various substances are at atmospheric pressure. Nobelium is the tenth transuranic element and is the penultimate member of the actinide series. Natural boron consists primarily of two stable isotopes, 11B (80.1%) and 10B (19.9%). In nuclear industry cadmium is commonly used as a thermal neutron absorber due to very high neutron absorption cross-section of 113Cd. Astatine is the rarest naturally occurring element on the Earths crust. The regular arrangement at an atomic level is often reflected at a macroscopic level. Bismuth is a pentavalent post-transition metal and one of the pnictogens, chemically resembles its lighter homologs arsenic and antimony. Osmium is a chemical element with atomic number 76 which means there are 76 protons and 76 electrons in the atomic structure. It is by mass the most common element on Earth, forming much of Earths outer and inner core. Thorium is a naturally-occurring element and it is estimated to be about three times more abundant than uranium. To calculate the density, divide the weight by the volume: 9 g / 37.5 cm3 = 0.24 g/cm3 = 240 kg/m3. It is a noble metal and a member of the platinum group. Since the number of atoms in a single unit cell of Zn and S is the same, it is consistent with the formula ZnS. Discoverer: Coster, Dirk and De Hevesy, George Charles, Discoverer: Elhuyar, Juan Jos and Elhuyar, Fausto, Discoverer: Noddack, Walter and Berg, Otto Carl and Tacke, Ida. Ratios of less than 1:1 are observed when some of the octahedral holes remain empty. Rubidium is a soft, silvery-white metallic element of the alkali metal group, with an atomic mass of 85.4678. Updated on March 28, 2019. Molybdenum is a chemical element with atomic number 42 which means there are 42 protons and 42 electrons in the atomic structure. Magnesium is a chemical element with atomic number 12 which means there are 12 protons and 12 electrons in the atomic structure. Zirconium is widely used as a cladding for nuclear reactor fuels. Mendelevium is a metallic radioactive transuranic element in the actinide series, it is the first element that currently cannot be produced in macroscopic quantities. A FCC unit cell contains four atoms: one-eighth of an atom at each of the eight corners (818=1(818=1 atom from the corners) and one-half of an atom on each of the six faces (612=3(612=3 atoms from the faces).
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