Physical Science: Assesment on bonds and chemical reactions

Antoine Lavoisier

Lavoisier established that the total mass of the products always equal the total mass of the reactants. He also established that the gas produced by heating mercury oxide was a component of air

Difference between compounds and elements

An element is a pure substance made up of only one type of atom, while a compound is a substance formed by chemically combining two or more different elements in fixed proportions

Chemical formula

A chemical formula shows what element a compound contains and the exact number of the atoms of each unit that compound has.

Metals on periodic table

most metals are found on the left side of the periodic table

Nonmetals on the periodic table

Most non-metals are found on the right side of th periodic table (excluding hydrogen which is on the left side)

Sharing electrons (covalent bond)

covalent bond, holds the atoms together as a molecule. A covalent bond happens if the attractions are strong enough in both atoms and if each atom has room for an electron in its outer energy le

Single double and triple bond

A single bond is formed when two atoms share one pair of electrons, whereas a double bond is formed when two atoms share two pairs (four electrons). Three pairs of electrons (six atoms) are shared to form triple bonds. Valence electrons are the electrons that share a pair of electrons.

Ion

an ion is a charged particle that has either less or more electrons then protons

Oxidation number

An oxidation number is a positive or negative number that indicates how many electroms an atom has gained, lost or shared to become stable

Anion

a negatively charged ion

Cation

a positively charged ion

Reactants

Starting substances that react

Products

The new substances produced

Chemical equation

A chemical equation is a way to describe a chemical reaction using chemical formulas and other symbols. Chemical equations quickly convey information such as the states of matter of the reactants and products.

Combustion reaction

A combustion reaction is something burning the process of burning (combustions) involves the combination of a substance with oxygen occurs when a substance reacts with oxygen to produce energy in the form of light and heat

Synthesis reaction

A synthesis reaction is when two or more substances combine to form another substance A+B-- AB

Catalyst

A catalyst is a substance that speeds up a chemical reaction without being permanantley changed itself

Inhibitors

Inhibitors are substances used to slow down the rates of chemical reactions or prevent a reactiion from happening

Equilibrium

An equilibrium is a state in which foward and reverse actions or processes proceed at equal rates

Combustion reaction

A combustion reaction is something burning the process of burning (combustions) involves the combination of a substance with oxygen occurs when a substance reacts with oxygen to produce energy in the form of light and heat

Synthesis reaction

A synthesis reaction is when two or more substances combine to form another substance A+B-- AB

Double displacement

A double displacement is where the positive ion of one compound replaces the positive ion of another to form two new compounds

Reaction rate

A reaction rate is the rate at which reactants turn into products

Exergonic reactions

Exergonic reactions are chemical reactions that release energy

Exothermic reactions

An exothermic reaction is where energy is given off primarily in the form of thermal energy

Endogonic reactions

An endogonic reaction is a reaction where a chemical reaction requires more energy to break bonds then is released when new ones are formed

Endothermic reaction

An endothermic reaction is where energy needed to keep a reaction going is in the form of thermal energy

Decomposition reaction

A decoposition reaction occurs when one substance breaks down into two or more substances AB--- A+B

Single displacement

Single displacement is when one element replaces another in a compund A-- BC= AC+B

Conservation of mass

matter is not created or destroyed, but conserved in a chemical reaction. This became known as The Law of Conservation Mass This means that the total starting mass of all reactants is equal to the total final mass of all products