Explanation of change in trend of density of elements in modern periodic table?
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The order of elements in the periodic table is determined by their atomic number, or number of protons (positively charged particles. The nucleus of the element is made up of protons and neutrons (neutral subatomic particles), and nearly all of the mass of the element resides here. \n\nElectrons "circle" the nucleus to even out the charge of the atom. The electrons organize themselves in layers, with a certain number of electrons in each layer. These layers are also referred to as the valence of the electron. The first layer has 2 electrons, the second and third have 8, the fourth has 18... These layers are what give the atom its volume.\n\nSince density is mass/volume, there isn't a linear relationship for density in each successive element, but the trend is density increases from left to right and top to bottom.
8701
You need to look at a Periodic Table. The farther to the left of the table an element is, the more metallic it is.
44826
Copper is #29 on the period table (yes, 4th period), but notice it's average atomic mass is 63.55.  Since electrons weight practically nothing, that means the weight of the protons and neutrons is 63.55.  Since it is #29, it has 29 protons by definition.  So on average it has 63.55 - 29 = 34.55 neutrons.\n\nRemember that though an element has roughly the same number of neutrons as protons, each atom can have a different number of neutrons.  These are called "isotopes".  But on average, copper has 34.55, according to the periodic table I've cited below.
714340
look up the periodic table...duh
980879
You need to look at the radius of the atom, and the number of protons in the nucleus.\n\nGroups I and 2 in the Periodic Table have large atoms, with good screening and low IE values.  The transition metal atoms are smaller, and the outer electrons are therefore harder to remove.
368567
You might be referring to brass, which has a density of 8.5 g/ml.\n\nBronze with 11% tin has a density of 8.1 g/ml.\n\n\nI would guess the brass, since it is more commonly used.
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Whe elements are heated the electrons in the atoms in the element gain more energy thus move a level(energy level or electron rings) upper and away from the nucleus this is never for long as they loose their energy and go back a level back during this time(when the electron is moving back to its enrgy level thats the lower level) it emitts energy of different wavelengths in other words photohs of differenet wavelengths thus you see different coulors.
910706
so you plot the proton number on the y-axis, and the different melting points of the elements across the x- axis.. actually are sure it has to be a bar graph.. i think a line/scatter graph would be more accurate maybe?
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Density is simply mass per unit volume.  The density of a substance is directly related to the atomic weight of the element composing it, ie., elements with higher atomic weight can be thought of as being “heavier”.   Another way of stating this is that equal volumes of two different substances have different densities because each different substance has a different mass (ie, atomic weight) and crystal structure.  There are many types of units which can be used to measure the mass of a substance (pounds, grams, etc.), just as there are many types of units which can be used to measure volume (cubic feet, cubic centimeters, etc.).  The standard units of measure for density are grams/cubic centimeter.  \n\nDifferent minerals or rocks can vary greatly in density, depending on their chemical make up.  Density is such a characteristic property of a substance that it may be used to identify the substance.  Geologists have found it useful to develop a system of comparing densities of different minerals or rocks by calculating a numerical value without units known as “specific gravity”.  The specific gravity is the weight of a substance compared to an equal volume of water.  Water is chosen as the substance for comparison because by definition it has a density of 1 gram per cubic centimeter (at 4o C), and also because it is such a common substance.  For example, compare the density of a rock like granite to water:  a cubic foot of water weighs 62.5 pounds and a cubic foot of granite weighs 168 pounds.  The specific gravity of granite is:   168 / 62.5  =  2.7.   Granite is 2.7 times heavier than water.
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→ Atomic radius decreases → Ionization energy increases → Electronegativity increases →\n\nIn general, the degree of electronegativity decreases down each group and increases across the periods, as shown below. Across a period, non-metals tend to gain electrons and metals tend to lose them due to the atom striving to achieve a stable octet. Down a group, the nuclear charge has less effect on the outermost shells. Therefore, the most electronegative atoms can be found in the upper, right hand side of the periodic table, and the least electronegative elements can be found at the bottom left. \n\nGenerally speaking, atomic ionization energies decrease down a group of the periodic table, and increase left-to-right across a period. Ionization energy exhibits a strong negative correlation with atomic radius.
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The density, the atomic structure, and the state of matter it is in.
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If you have your periodic table handy, look at the key for the table, where it will tell you which corner of each element's block has the atomic radius.  You will notice that atomic radius tends to increase as you go down the rows of the table.  Makes sense; More electrons means a larger atom.  As you go from right to left, however, you will see that, in any one row, the radius decreases until you get to about the middle of the row; then the radius begins to increase with the atomic weight.  On any row, the element at the left end (lower atomic weight) has a larger diameter than the one on the right end (higher atomic weight).  All of this out of the way, Beryllium is larger than Carbon, which is in turn, larger than Nitrogen.
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Atoms want to be like a "noble gas" with a filled outer shell.  I think it has to do with being in a stable state.  For Mg, it's a lot easier to drop 2 electons to look like Ne rather than gain 6 to look like Argon.\n\nThis very basic premise only works for things on the "sides" of the table.  The transition elements in the middle are a bit different.
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no, the densest metal is NOT uranium, it is the heaviest natural element, but it is the the most compacted, and therefore, dense, the densest element is Iridium at 22.5 g/cm3. uranium's density is only 18.95 g/cm3 at 20 C.
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Periodic Table is in order of increasing atomic no. so\n\n1st Step: find the placement of the element, in the present case it is on third place so no. of protons is three.\n\n2nd Step: In the Periodic Table, number of electron is always equal to number of protons so far three protons of Lithium there will be three electrons.\n\n3rd Step: Periodic Table also give atomic weights of the elements. Simply atomic weight is equal to sum of number of protons and nutroms.\n\n4th Step: Note the atomic weight of the element. Most of the elements in Periodic Table show atomic weights in fractions. In the case of Lithium it is 6.9 \n\n5th Step: Convert the fractional figure into nearest whole number. In case of Lithium it is 7\nNote:In the Periodic Table atomic weight is average of all isotopes (different atomic weights of same element). The nearest whole number refers to the most abundent  or the common atom (Isotop).\n\n6th Step: Subtract atomic number (protons) from atomic weight (neutron=proton), the difference is number of neutrons. In Lithium 7-3=4 so there are 4 neutrons
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You need to know more than just the electron configuration.  There is contraction from left to right on the periodic table, plus additional periodic trends that must be considered.   \n\nEven more importantly, you need to define whether you are looking for the largest element IN ITS NATURAL  STATE (i.e. Cl2, Hg metal, etc) or AS THE ION.   Atomic and ionic radii differ.\n\nMore clarity is needed here.
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As you move down a family in the periodic table, the number of shells of electrons increases  (draw the Bohr- Rutherford diagrams), and the atoms increase in size.\n\nThe larger the atom, the further the valence electrons are from the nucleus, and the weaker the hold it has on them. So, it becomes easier to remove a valence electron.\n\nSince IE measures the amount of energy needed to remove an electron from an atom, this value will decrease, moving down the family from He to Rn.