Periodic table origin and development

Discovered the Law of triads

Grouping of elements in three. The atomic mass of the middle element is the average of the other two.

Lithium has the atomic mass of 7, sodium has 23, and potassium has 39. If you add the 1st and 3rd one and divide it by 2, what is the mean of 1 and 3?

The first person to organise elements by atomic weights.

Plotting a helical graph of the elements around a cylinder with a circumference of 16 units corresponding to the weight of oxygen.

devised the first periodic table and arranged the elements according to increasing weights

John Newlands arranged the elements according to increasing weights and observed that the properties of the elements are repeated after an interval of eight elements.

__ created the first periodic table and was shortly followed by ?

They proposed that certain properties periodically reoccur

Meyer formed his periodic law based on ____ or ____, which is the atomic mass divided by the density in solid form.

Rearranged the elements in the periodic table according to increasing atomic number.

According to the increasing atomic number. This is the basis of the modern periodic table

discovered the transuranium element?

It has the atomic number of 92-102.

The lanthanide and actinide

This law states that when elements are arranged in the order of increasing atomic number, elements with similar properties appear at periodic intervals.

Period or series of the elements in the periodic table

Vertical column is the ____ of elements

The ____ indicates the occupied highest main energy level of the elements.

the elements belong to the same period or series

The Lanthanide and actinide series projected perpendicular to the plane of the periodic table

Chemical Families

These are found in the outermost or highest main energy level.

1-18 groups and IA-VIIIA groups

International union of pure & applied chemistry (IUPAC)

older notation - US usage

Single electron in their outermost energy level

soft, silver-white, shiny metals

it can be cut with a knife

good conductors of heat and electricity

can bond readily with other substances

they are very reactive

react violently with water

can easily burn and may explode

Family 1-Alkali Metals

Never found in nature as uncombined elements

Have no valence electrons

Not as reactive as the other

Some are used and industries as alloys and some are important elements found in the human body

Have properties similar to one another and to other metals ut they are different from the properties of any other family

Also good conduct of heat and electricity

Brightly Colored and often used as color paint

Some are used for jewelry making, and component of some measurements tools

Can form many different compounds when losing one or more

Has 3 Valence electrons

Hard and brittle and never uncombined in nature

Visually combined with Oxygen

Often used for glass wares and cleaning compounds such as borox

Other metal elements are often used as components in the production of cars, trains, and planes

A metalloid (but in the boron family, the other is metal)

A non mental and the element that is the basic of your life

Two elements, silicon and germanium are metalloids, while ___ is non-metal

Almost all compounds that are important for our body have this

Metals are used for making cans that are tin and in production of paint and component in gasoline but removed because of its harmful effects.

This makes up 75% of the atmosphere and is used for the production of pesticides, explosives, medicines, and dyes

Belongs in family 15- Nitrogen family

an active non-metal used in making tips of matches and flares

Belongs in family 15- Nitrogen family

an ingredient in many insecticides

Belongs in family 15- Nitrogen family

used in making alloys

Has five valence electrons. The elements in this family: makes up 75% of the atmosphere, used for:

Pesticides

Explosives

Medicines

dyes

making tip of matches and flames

ingredient for insecticides

making alloys

The most abundant element in the Earth’s crust

Very important in all forms of life

Can form compounds with other elements or form a molecule by bonding itself such as ozone

Family 16- Oxygen family

Part of family 16 - Oxygen Family which is an extremely rare element

Have 7 valence electrons

Most active non metals

Never found in nature

Can share or gain 1 electron with other atoms to form compounds

Bond with other atoms to form salts, an important component in making toothpaste, used to melt snow and ice on streets, and used in photographic film

Bromine is one of the few liquid element while iodine and the other metalloid astatine are solids

Normally unreactive

Do not readily form compounds with other elements

Also called as inert gases

Among noble gases, helium has 2 valence electrons while some have 8 electrons

Some of the noble gases are used as theatrical effects and colored signs, and neon lights

Radon is used to treat certain cancers

Argon and xenon are used in light bulbs and lamps

This is made up of soft, malleable metals that have high luster and conductivity. They are used in making various alloys and high-quality glass in industry.

Composed of elements which are radioactive. Uranium is used as fuel in nuclea powered electric generators

Atomic Size, Ionization Energy, Electron affinity, Electronegativty

Defined by the atom’s atomic radius (One half the distance from the two nuclei of two adjacent atoms).

Energy that is needed to remove the valence electron

Energy released or required when electrons are added to an atom in the gaseous phase

The tendency of the atoms to attract electrons towards itself in the chemical bond

Developed the electronegativity values presented in the periodic table

elements can be metal, non-metal, and metalloids

It states that atoms tend to gain, lose, or share electrons until they are surrounded by eight valence electrons.

Octet Rule

These are stable and have high ionization energy. The s and p orbitals are completely filled.

Proposed the Lewis Electron Dot Structure

It indicates the number of valence electrons in an atom represented by dots scattered on four sides of the atomic symbol