Chemistry chapter 1

Protons ( + )

a subatomic particle with a positive electrical charge: found in every atomic nucleus of every element

Neutrons (no charge)

a subatomic particle inside the nucleus of every atom alongside protons but have a neutral electric charge

Electrons ( - )

subatomic partical also found in all atoms, unlike P & N, they are elementary particals with an negative charge

Isotope

member of a family of an element that have the same number of protons but diffrent number of neutrons

Nucleon

Consits of protons and neutrons, a central region that is positivley charged

Group

A vertical column in the periodic table of the chemical elements that contains elements with similar properties and the same number of valence electron

Number of energy levels

how many rings from the middle period

period

A horizontal row in the periodic table of elements, indicating the number of energy levels in the atoms of the elements in that row.

Valence Electrons

Electrons on the outermost shell of an atom that determine its chemical properties and bonding behavior.

Families

Vertical columns in the periodic table that group elements with similar properties and the same number of valence electrons.

Alkali Metals

Group 1:one valence electron, shiny solids, very soft malleable and ductile, reacts easily with water and other substances

Alkaline earth metals

Group 2: two valence electrons, shiny solids, mallable and ductile, reacts with oxygen to form subtances called oxides

Halogens

Group 17: seven valence electrons, chlorine and fluorine are gases, bromine is a liquid and iodine is a solid. Reacts with metallic elements to form subtances called salts

Noble Gases

Group 18: eight valence electrons except helium with two. colourless gases, very unlikly to take part in chemical reactions

electron dot diagram

no rings, has only the atmoic symbol of the element, electrons for the valence are around the symbol

Ion

Any atom/group of atoms that carries a positive or negative electrical charge

Cation

Positively charged ion that has fewer electrons that protons

Anion

Negatively charged have more electrons than protons

gas discharge tube

an experiment where a high voltage is applied to a partially evacuated glass tube filled with gas, causing the gas to conduct electricity and emit light

cathode rays

streams of electrons that travel in a vacuum tube from a negatively charged cathode to a positively charged anode

subatomic particle

particles that are smaller than an atom and make up all matter

atomic number

the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.

mass number

the total number of protons and neutrons in an atom

stable octet

a configuration of eight electrons in an atom's outermost shell, or valence shell

Ionic compound

compounds made up of ions that form charged particles when an atom (or group of atoms) gains or loses electrons.

binary ionic compound

a chemical compound made of a metal cation and a nonmetal anion

Ionic bond

formed between two or more atoms by the transfer of one or more electrons between atoms.

crystal lattice

the symmetrical three-dimensional arrangement of atoms inside a crystal.

molecule

a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.

molecular compound

a substance made up of two or more nonmetal atoms that are held together by covalent bonds. 

covalent bond

the interatomic linkage that results from the sharing of an electron pair between two atoms

Daltons Theory

1803: 1) Elements consist of indivisible small particles (atoms). (2) All atoms of the same element are identical; different elements have different types of atom. (3) Atoms can neither be created nor destroyed.

Bohr’s Model

electrons orbit the nucleus at fixed energy levels