Enthalpy Changes The total chemical energy inside a substance is called the enthalpy (or heat content) When chemical reactions take place, changes in chemical energy take place and therefore the en...
Effects of Bonding & Structure on Physical Properties Different types of?structure?and?bonding?have different effects on the?physical properties?of substances such as their?melting?and?boiling ...
Lattice Structures Most ionic, metallic and covalent compounds are?crystalline lattice The ions, atoms or molecules are arranged in a?regular and repeating arrangement Giant ionic lattices An?ionic...
Gases: Ideal Gas Law & Equation Kinetic theory of gases The kinetic theory of gases?states that molecules in gases are constantly moving The theory makes the following assumptions: The gas mole...
Gases: Gas Pressure Gases?in a container exert a?pressure?as the gas molecule are constantly?colliding?with the wall of the container Gas particles exert a pressure by constantly colliding with the...
Dot & Cross Diagrams Dot and cross diagrams?are diagrams that show the arrangement of the outer-shell electrons in an?ionic?or?covalent?compound or element The electrons are shown as dots and c...
A-Level大考今日放榜，同學們可以抓緊時間查詢自己的分數。出分后，AS階段的考生若對此次A-Level成績滿意，即可著手準備2023年的留學事宜；A2階段的考生若成績滿足院校申請要求，那么后續只需等待相應院校的確認...
此前由于疫情原因，各個國際大考相繼出現考試形式的更改問題，其中個別地區的A-Level大考就因此轉換為POE或TAG形式，許多同學不免擔憂評估出分會導致高分通脹情況。 同學們的擔憂是否會成為既定事實？相信隨著今...
Comparing Bonds to Intermolecular Forces Intramolecular forces Intramolecular forces?are forces?within?a molecule Ionic bonding?is the?electrostatic attraction?between?positive?(cations) and?negati...
van der Waals' Forces & Dipoles Covalent bonds are strong?intramolecular forces Molecules also contain weaker?intermolecular forces?which are forces?between?molecules These intermolecular force...
Polarity & Dipole Moments Electronegativity?is the ability of an atom to draw a pair of electrons towards itself in a covalent bond Electronegativity?increases?across a Period and?decreases?goi...
Hydrogen Bonding Hydrogen bonding Hydrogen bonding?is the?strongest?form of?intermolecular bonding Intermolecular bonds are bonds?between?molecules Hydrogen bonding is a type of?permanent dipole – ...
