Chemistry Module 2 yr 11

meaning of mole

a name of a certain number of things (602 hexillion things)

mass of 1 mole of a substance (PT mass)

molar mass/ formular mass

number of moles (n)

mass/molar mass (m/M)

number of moles (n)

number of atoms or molecules/ Avogadro's constant

number of atoms or molecules

Avogadro's constant x number of moles

Avogadro's number

6.022x10^23

Avogadro's law states

equal volumes of gases, at the same temperature and pressure contain equal numbers of gas molecules

empirical formula

simplest ratio of atoms or ions in a compound

molecular

number of atoms in a molecule

percentage composition

the percentage by molar mass of each element in a compound

limiting reagent

the reactant that is completely used up in a chemical reaction

excess reagent

the reactant which is not completely used up in a chemical reactions

aspects of chemical reactions

reacting species

products of reactants/ reaction

physical states of various substances

amount of each substance

reactants

the chemicals you start with in a chemical reaction

products

the chemicals you end up with in a chemical reaction

state indicators

(s) = solid

(g)= gas

(l)= liquid

(aq)= aqueous

balanced equation

equation describes a chemical reaction with exactly the same number of atoms of each element on each side of the equation

liquid vs aqueous

liquid is the melted physical state of a substance (as apposed to solid or gas)

aqueous means dissolved in water

one compound (combination reaction)

element+element

element+compound

compound + compound

compound (decomposition reaction)

element + element

element + compound

compound + compound

displacement reaction

element + ion compound or element + acid > element + ionic compound

Combustion reaction

compound of C,H, O + O2 > CO2 + H2O

precipitation reaction

2 ionic compounds > two ionic compounds (one solid)

acid +metal

salt + hydrogen

acid + base

salt + water

acid + carbonate

salt + water + carbon dioxide

rusting reaction

Fe + O2 > FeO2

conservation of mass

it is the idea that atoms cannot be destroyed or created during chemical changes

Stoichiometry

deals with calculations of quantities involved in chemical equations

solution

the name given to the complete system of one substance dissolved in another

solvent

the substance in to which another is dissolved- 'the stuff that does the dissolving'

solute

the substance being dissolved by the by the solvent

saturation

the point to where no more solute can be dissolved in the current conditions (temp/psi)

supersaturation

it is possible to dissolve more solute in the solution than normal if the solvent is heated it can dissolve more solute, if cooled carefully it can hold more solute than normal at a given temp.

solubility

a measure of the amount of solute that will dissolve in a given solvent

molarity

the number of moles per liters of solution

concentration

describes a solution with a large amount of solute /L

diluted

describes a solution with a small amount of solute /L

mass by volume

concentration = mass of solute/ volume of solvent

percent by mass

concentration = mass of solute/ mass of solution

percent by volume

concentration= volume of solute/ volume of solution

parts per million

1ppm = 1mg/L or 1mg/kg

concentration = mass of solute(mg)/ mass of solution(kg)

dilution

C1V1= C2V2

properties of gas

-may be compressed

-extend to fill container uniformly

-have low density

- may be mixed

-when confined, exerts constant pressure

the ideal gas model

pictures gas as a consisting of a large number of independent and widely spaced molecules, moving in random and chaotic fashion at high speed. individual molecules move in straight lines until they collide with other molecules or the wall of the container

measuring gases

pressure is a measure of the force exerted per area

pressure= force/ area p=f/a

boyle's law

p /alpha 1/v

p1v1 = p2v1

charles law

V1/T1 = V2/T2