Unit 2 chemistry Gr.11 Ultimate Study Guide

Diatomic Elements

Elements that exist naturally as diatomic molecules, remembered by the mnemonic HOFBrINCl: H2, O2, F2, Br2, I2, N2, Cl2.

Monoatomic Elements

Elements that exist as single atoms at room temperature, mostly solid except for mercury (Hg) which is a liquid.

Ionic Compounds

Compounds formed from the electrostatic attraction between cations and anions, which are solid at room temperature.

Molecular Compounds

Compounds formed by covalent bonds between non-metals, with small molecules typically being gases at room temperature.

Skeleton Chemical Equation

An unbalanced chemical equation showing correct formulas and physical states without stoichiometric coefficients.

Balanced Chemical Equation

A chemical equation where the number of atoms is equal on both sides, adhering to the law of conservation of mass.

Synthesis Reaction

A reaction where two or more reactants combine to form a single product compound, represented as A + B → AB.

Decomposition Reaction

A reaction where a single compound breaks down into two or more simpler products, represented as AB → A + B.

Combustion Reaction

A reaction where a substance reacts rapidly with oxygen, producing heat, light, and often oxides.

Single Displacement Reaction

A reaction in which an element displaces another in a compound, represented as A + BC → B + AC.

Double Displacement Reaction

A reaction where the cations or anions of two compounds exchange places to form new compounds, represented as AB + CD → AD + CB.

Precipitate

An insoluble solid that forms from a reaction in an aqueous solution.

Neutralization Reaction

A chemical reaction between an acid and a base producing water and a salt.

The Activity Series

An empirical list ranking metals and hydrogen by their reactivity; more reactive metals can displace less reactive metals.

Hydrocarbon

An organic compound composed solely of hydrogen and carbon atoms.

Electrolysis

The process of using electrical energy to induce a non-spontaneous chemical reaction, often breaking compounds into their elements.

Soot

Fine particulate matter predominantly composed of unburned carbon produced from incomplete combustion.

Law of Conservation of Mass

The principle stating that matter cannot be created or destroyed in a chemical reaction; total mass of reactants equals total mass of products.