He Periodic table It is a table of all the items that we know today. The elements are placed in order of atomic number (number of protons in the nucleus). The periodic table is a way of listing and organizing the elements.
The rows of the periodic table are called periodsand the columns are known as groupsThe groups have similar physical and chemical properties.
He cluster An element's membership is determined by the number of electrons it has in its outer shell. Elements in group 1 have one electron in their outer shell, those in group 2 have two electrons in their outer shell, and those in group 0 have all other shells with 8 electrons (or 2 in the case of helium).
How many elements are there in the periodic table?
The periodic table currently contains 118 different elementsEach square represents an element. Elements with similar properties are grouped together.
How are elements numbered on the periodic table?
Elements are listed from left to right in order of how many protons their atoms contain. Hydrogen is the first element on the periodic table, as its atom contains one proton.
Metals are on the left of the table, metalloids are in the middle, and nonmetals are on the right.
Each square of the periodic table contains information about the element.
Who invented the periodic table?
The periodic table was invented by Dmitri Mendeleev In 1869, he was the first scientist to arrange the elements according to their atomic mass. Mendeleev was so adept at spotting patterns that he left empty spaces for undiscovered elements.
The modern periodic table is slightly different from the one created by Mendeleev, as it is arranged by atomic number, not atomic mass.
Chemical symbols that do not resemble their name
Each element has a chemical symbol that is the same in every language. Some are obvious, such as Li for lithium, but others are harder to decipher. The first letter is always capitalized and the second is lowercase.
Tungsten has the symbol W, this is because tungsten means tungsten in German.
Lead has the symbol Pb, which comes from the Latin word plumbum.
Mercury is Hg
Iron is Fe
Elements of group 1 and 2
The red column is known as Group 1 and the orange column is known as Group 2. Elements in these groups are known as reactive metals. Pure sodium bubbles and flares when placed in water, potassium bursts into flames in water, and cesium explodes when added to water. The reactivity of the elements increases as you go down the column.
Transition metals
The yellow block of elements in the middle of the table are known as transition metals. These elements are very useful as they conduct electricity and are mostly solid at room temperature.
Halogens – Group 7
The halogens are the light violet elements. The halogen column is the only column that contains solid, liquid, and gaseous elements. Fluorine is a yellow gas, bromine is a red liquid, and iodine is a violet solid.
Halogens react with group 1 metals to form compounds. An example of this is the reaction of sodium with chlorine to form sodium chloride.
Noble gases – Group 0
These are the dark violet elements. They are not reactive because they have an outer shell full of electrons and are very useful.
Noble gases are monatomic, they exist as individual atoms.
Neon is used for neon signs, helium is used in balloons, argon is used in 3D printing, welding, lasers, and has many other manufacturing uses.
Radioactive elements
Many of the elements at the bottom of the table (in green) are radioactive.
Fun facts about the elements
The atomic number of an element is the number of protons that an atom of the element contains.
In ancient times, radium was used to paint glow-in-the-dark hands on clocks.
Lithium is a metal, but it is so soft that it can be cut with a knife.
Helium is lighter than air, which is why it is used to fill helium balloons.
Argon is used on the inside of double-glazed windows because it does not conduct heat.
Rocks containing barium glow at night.
Mercury is the only transition metal that is liquid at room temperature.
Sapphires are blue because of iron.
Bismuth is diamagnetic. Magnets repel it.
Neon is the least reactive element on the periodic table and is used in neon signs.
Titanium is very strong and very, very light!
Ideas for learning about the periodic table
Teach Beside Me has an amazing Periodic table of battleships game.
Make atom models with paper plates, we use them for Learn about isotopes.
Sing the periodic table song, this one gets stuck in my head for weeks!
Last updated on May 10, 2023 by Emma Vanstone
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