Honors STEM: Chemical Bonds and Chemical Reactions (Ava)

Please refer to chapter 18 and 19 in your text book. Use the infographic that you created as a study guide for chapter 19. topics: Lavoisier The conservation of mass Chemical equations Coefficinets Classify chemical reactions Energy and Chemical Reactions Reaction rate Collision Model Volume and Pressure Equilibrium Catalyst and inhibitors

chemical reaction

a change in which one or more substances are converted into new substances

reactant

the starting substance that reacts

product

the new substance produced

Antoine Lavoisier

a French chemist who studied chemical reactions using scientific methods

Antoine Lavoisier’s discovery

matter is not created or destroyed but conserved in a chemical reaction; combustion reaction; law of conservation of mass

law of conservation of mass

the total starting mass of all reactants equals the total final mass of all products

chemical equation

a way to describe a chemical reaction using chemical formulas and other symbols

types of chemical reactions

combustion reactions, synthesis reactions, decomposition reactions, single displacement, double displacement

combustion reactions

occurs when a substance reacts with oxygen to produce energy in the form of heat and light

synthesis reactions

two or more substances combine to form another substance (A+B→AB)

decomposition reactions

occur when one substance breaks down, or decomposes, into two or more substances (AB→A+B)

single displacement

one element replaces another element in a compound (A+BC→AC+B)

double displacement

the positive ion of one compound replaces the positive ion of another to form two new compounds (AB+CD→AD+CB)

exergonic reactions

releases energy

exothermic reactions

gives off thermal energy

endergonic reactions

absorbs energy from their surroundings; requires more energy to break bonds than is released when new ones are formed

endothermic reactions

absorbs thermal energy

reaction rate

the rate at which reactants change into products

collision model

states that atoms, ions, and molecules must collide in order to react

equilibrium

a state in which forward and reverse reactions or processes proceed at equal rates

catalyst

a substance that speeds up a chemical reaction without being permanently changed itself

inhibitor

a substance that is used to slow down the rates of chemical reactions or prevent reactions from happening at all

compounds

two or more different types of atoms that are chemically bonded

elements

molecules made up of only one type of atom

molecules

neutral particles that form as a result of electron sharing

single bond

shares one pair of electrons, 2 atoms

double bond

shares two pairs of electrons, 4 atoms

triple bond

shares three pairs of electrons, 6 atoms

ion

a charged particle that has either more or fewer electrons than protons

cation

positively charged ion

anion

negatively charged ion

oxidation number

a positive or negative number that indicates how many atoms an electron has gained, lost, or shared to become stable; same as group or family

subscript

indicates number of atoms in element

coefficient

represents the number of units of each substance taking part in a reaction

chemical formula

shows what elements a compound contains and the exact number of the atoms in each element in the unit of that compound

chemical bond

the force that holds atoms together in a compound

ionic bond

bonds involving the transfer of electrons between two atoms; formed by nonmetals and metals

covalent bond

bonds involving the sharing of a pair of electrons between two atoms; formed by two nonmetals

oxidation

the loss of electrons

reduction

the gain of electrons

reversible action

occurs in both the forward and reverse directions

compound vs molecule

made of 2+ different elements chemically bonded vs groups of atoms bonded which could be the same or different elements

non polar bond

a non-polar bond is a covalent bond in which electrons are shared equally by both atoms

Polar bond

A bond in which electrons are shared uniquely, ending with a slightly positive and slightly negative end

Polar molecule

The unequal sharing of electrons result in a slightly positive end and slightly negative end

non-polar molecule

a molecule that does not have opositley charged ends

binary compounds

formulas composed of 2 elements

polyatomic ion

Positively or negatively charged covalently bonded group of atoms

precipitape

an insoluble compound that comes out of solution during a double displacement reaction