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Periodic Table
The Periodic Table is a tabular arrangement of the elements in increasing order oftheir atomic numbers, so that elements with similar properties are in the same column. There are 18 columns, called groups, and seven rows, which are called periods, in the modern periodic table. Questions about the Periodic Table: its history and creation, trends, groups/families, and periods are asked in our Periodic Table category.
11,356 Questions
What block is Ca in the periodic table of elements?
Calcium (Ca) is located in the 4th block of the periodic table of elements, specifically in the s-block. It is a metal that is commonly found in nature and is essential for various biological processes in living organisms.
Nearly all of the palladium found in nature is of six stable isotopes. There are traces of a radioactive isotope, 107Pd, also found, but the quantity is insignificant. Like all elements, palladium has synthetic radioactive isotopes.
What element has 12 protons and 10 neutrons?
Any atom, ion, or isotope with 12 protons is going to be magnesium. Only the number of protons in the nucleus will determine the element. But with the information about the number of neutrons, the specific isotope can also be determined - 22Mg.
What is the periodic table of elements organized by?
In the most usual modern form of a periodic table, the arrangement is by atomic number from left to right and in as many rows or periods as the number of the highest electron shell in the atom that contains at least one electron in a neutral atom. The only two elements in the first periods are at the far left and far right in columns 1 and 18, and the second and third periods skip columns from 3 through 12. In the sixth and seventh periods, the entry in column 3 is usually a footnote referring to a separate row at the bottom of the table where the atomic number sequence continues before adding an element to column 4.
Chemical reactions involve changes in the electron configuration of atoms, not the nuclei. In contrast, nuclear reactions alter the nuclei of atoms by changing the number of protons, which can result in the transformation of one element into another. Chemical reactions do not have the ability to change the identity of elements based on the number of protons in the nucleus.
Why do 'd' block elements exhibit variable valencies?
The "d" block elements have electrons in a "d" in a lower shell than the valence electrons in the "s" orbital. These "d" electrons can be moved to the outer shell to give a metal a higher valence then the value of 2 that might otherwise be expected. Osmium can have a valence as high as 8. Additionally, the outer shell electrons can be moved from the "s" orbital down to the "d" orbital to give a metal a lower valence, perhaps the most notable case of this is silver which almost always forms a 1+ ion rather than 2+.
How does density change as it goes down the group and across the periods?
Among gaseous and liquid nonmetals, as atomic number increases, London dispersion forces increase with the number of electrons, resulting in higher polarity and intermolecular attraction. Therefore, density generally increases as atomic number increases.
The majority of metals have higher densitiesthan the majority of nonmetals. The high density of most metals is due to the tightly packed crystal lattice of the metallic structure. The strength of metallic bonds for different metals reaches a maximum around the center of the transition metal series, as those elements have large amounts of delocalized electrons in tight binding type metallic bonds.
However, other factors (such as atomic radius, nuclear charge, number of bonding orbitals, overlap of orbital energies, and crystal form) are involved as well.
What is so special about the group18 elements?
Group 18 in the periodic table is the last column on the periodic table. This family is known as the Noble Gases and is so special because of their inability to react. They have a full outer shell of electrons, which means they are very stable and can be found in nature as isolated elements.
What is element No 90 thorium?
Thorium can be used as fertile material (as ThO2) in nuclear power reactors; is a precursor of the fissile isotope 233U.
This type of reactor is called a breeder: the reactor produce more fissile material than it consumes. It is a very strange and important characteristic.
On which side does the isulators found in periodic table?
Insulators are found on the right side of the periodic table, specifically in the nonmetals and noble gas groups. They have high resistivity and do not conduct electricity or heat very well due to their electron structures.
What are the alkali metals and coinage metals?
Alkali metals are group 1 metals such as lithium, sodium, potassium, rubidium, cesium and francium.
Coinage metals are metals used in coin age to make coins. They are copper, gold and silver.
What is the lowest atomic number actinide?
The lowest atomic number actinide is actinium, with the atomic number 89.
Why 2nd ionization potential is greter than 1st ionisation potential of element?
In the first ionization an electron is removed from a neutral atom.
In the second ionization an electron is removed from a positively charged ion. Since electrons carry a negative charge and opposite charges attract it is more difficult (i.e. takes more energy) to remove.
Elements with atomic numbers greater than that of iron (26) are formed through a process called supernova nucleosynthesis, which occurs during the explosive death of massive stars. These elements are created through rapid neutron capture processes, leading to the production of heavy elements like gold, platinum, and uranium.
with an electron configuration that fills up to 2 electrons in their outermost energy level. This includes hydrogen and helium, which have one and two electrons in their outermost s orbital, respectively.
Two elements in the same chemical family can have the same spectrum?
True, elements in the same chemical family have similar electron configurations, which can result in similar spectral characteristics. For example, alkali metals like sodium and potassium have similar line spectra due to their similar outer electron configurations.
What is the chemical formula for technetium carbonate?
The chemical formula for technetium carbonate is Tc2(CO3)3.
Okay: so there's this "zigzag line" on the periodic table and all elements to the right of that line are nonmetals. A few touching the line are considered metalloids but look the right of that things and there are your nonmetals for you.
They are:
Hydrogen
Helium
Carbon
Nitrogen
Oxygen
Fluorine
Neon
Phosphorus
Sulfur
Chlorine
Argon
Selenium
Bromine
Krypton
Iodine
Xenon
Astatine
Radon
What is the atom with the atomic radius of 133?
133 what? what are the units here?
err.....i suppose its tht of Fluorine's......hey, if u find out if flourine's atomic radius is more thn tht of helium's, jus lemme know.
thnq
Noble gases actually have the most stable electronic configurations in the periodic table due to having a full outer shell of electrons. This full octet makes them less likely to react with other elements, earning them the name "noble gases."
What elements on the periodic table are named after discoverer?
Offhand I can't think of any that are directly named after their discoverer personally.
There are several named after scientists (curium, einsteinium, seaborgium, mendelevium, etc.), but those scientists did not discover these particular elements (Seaborg discovered, or at least participated in the discovery of, several elements, but seaborgium was not one of them; likewise for Curie and curium; Einstein didn't discover any elements).
There are some named after countries: francium and polonium were named after France and Poland... the countries where their discoverer, Marie Curie, was living and was born respectively.
Finally, there are at least two named after an employer: californium and berkelium were named by a team working at the University of California - Berkeley. ("At least" because while lawrencium is supposedly named after Ernest O. Lawrence, it was discovered at the Lawrence Radiation Laboratory, which was ALSO named after Ernest O. Lawrence, making it a bit ambiguous.)
There are currently how many periods on the periodic table?
There are currently 118 elements currently, with 20 man-made and 88 (not 92) naturally-occurring elements. *Since 23rd October 2008.
What solution is capable of dissolving gold?
Aqua regia, which is a mixture of two acids, will dissolve gold. Aqua regia is a mixture of concentrated nitric acid (HNO3) and concentrated hydrochloric acid (HCl), usually in a 1 to 3 ratio respectively. Aqua regia is one of the few acids that will dissolve both gold and platinum as well as other metals. Interestingly, neither hydrochloric acid nor nitric acid alone will dissolve gold, but together, they will!
Both acids do different jobs. Nitric acid actually dissolves a virtually undetectable amount of gold, which reacts with the hydrochloric acid to produce ions that are much more soluble. This frees the nitric acid to dissolve the gold further, and the reaction continues.
See the Web Links to the left for more information about aqua regia.
