类别 全部 - bases - acids - periodic - reactions

作者:Bharavi Chauhan 2 年以前

102

3U Chemistry

Chemistry covers a wide range of fundamental concepts and principles essential for understanding the behavior of matter. In stoichiometry, the quantitative relationships between reactants and products in chemical reactions are crucial, often involving mole-to-mole ratios and calculations of mass, volume, and concentration.

3U Chemistry

3U Chemistry

Reactions

Writing Chemical Equations
Solubility rules

shows you which elements are insoluble

Activity series

a list of decreasing order of their reactivity

Balancing equations

To even out the amount of an element on the other side of the reaction

types of reactions
Combustion (C2H2+O2=H2O+CO2)

can also be incomplete

Double displacement ( AB+CD=AD+CB)
Single displacement (A+BC=AC+B)
Decomposition (AB=A+B)
Synthesis ( A+B=AB)

Forces and Bonds

Lewis Structures and VSEPR Diagrams
VSEPR diagrams are used to predict the geometry of a molecule from the number of atoms that are bordering the central atom
Lewis structures show which atoms are bonded together in a molecule
Chemical Bonding and Electronegativity
Electronegativity is When an atom is bonded, it has the potential to draw individual electrons to itself.

Ionic bonds

Polar covalent bonds

Non-polar covalent bonds

Intramolecular Forces
Occur within the molecule

ionic

the transfer of one or more electrons between a metal and non-metal

Covalent

sharing of electrons between two non-metals

Intermolecular forces
Occurs between molecules

Hydrogen Bonding

Polar molecules but a hydrogen has to be bonded to a F, O, N

Dipole-Dipole

Polar molecules only are held together due to their partial charges

London Dispersion

Polar and non-polar molecules form temporary bonds by the constant movement of electrons causing a short-term charge imbalance

Stoichiometry

Acids and Bases
PH scale

it tells us how basic or acidic the solution is.

Bases

A base is a substance with a PH greater than 7 that can neutralise an acid by reacting with hydrogen ions.

Bronsted-Lowry theory, Arrhenius theory
Acids

With a PH less than 7, an acid is a molecule or ion capable of contributing a proton or, alternatively, forming a covalent bond with an electron pair.

Titrations
Used to determine the concentration of a solution
The relationship between the relative quantities of the reactants in a reaction.
Limiting and access reactants

Access Reactant

A reactant that remains after the reaction is complete

Limiting Reactant

A reactant that is completely consumed during a chemical reaction

Calculated using mole to mole ratio, mass, volume, concentration, molar mass

Gases

Gas stoichiometry
Ideal Gas Law

PV=nRT

STP and SATP

Gas Law
Gay-Lussak's Law

States that temperature and pressure are directly proportional while the volume remains constant

Charle's Law

States that temperature and volume are directly proportional as long as mass and pressure remain constant

Boyle's Law

States that pressure and volume are inversely proportional as the temperature and mass remain constant

Kinetic Molecular Theory
Particles of gas are in constant motion and collide with one another

Gas is mostly empty space

Pressure is exerted when particles hit the sides of the container while causing collisions

We assume that particles do not interact with each other

Average kinetic energy is proportional to the temperature

Periodic table

Element Properties
atomic weight is the number off neutrons
Atomic number is the amount of electrons and protons
Periodic table groups

alkali metals, alkaline earth metals, transition metals, metalloids, other metals, non metals, halogens, noble gases and rare earth elements

Periodic trends
First Ionization Energy

The energy required to move one of the loosely held electrons from the gaseous atom

Electron Affinity

When an atom can attract bonded electrons

Atomic Radius

The distance from the middle of the nucleus to the outermost shell. As the energy levels increase the radius does too