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The pH scale

This is an introduction to the pH scale. Explore the relationship between pH and hydrogen ion (H⁺) concentration. The-pH-scale...

Reaction enthalpies

Enthalpy change For a reaction Bonds Know that Breaking bonds always requires energy (never releases energy) Forming bonds always releases energy (never requires energy) Exothermic and endothermic process Breaking bonds is always an endothermic process (whether...

1. Naming inorganic compounds

First learn how to identify if a compound is covalent or ionic. You will need to know the periodic table You must be able to identify the non-metals, metals, and transition elements in the periodic table You must be able to categorize a compound as ionic or covalent...

4. Compounds with Polyatomic Ions

What are polyatomic ions? Ions are formed when neutral atoms gain or lose electrons. Similarly, a polyatomic ion is formed when a neutral molecule gains or loses electrons. A polyatomic ion is a charged group of atoms covalently bonded together. Majority of the...

1. Introduction to Chemical Kinetics

Energy Kinetics involves studying what makes chemical reactions happen. Every reaction that happens involves some energy exchange, whether it’s slow reaction such as iron rusting, or a faster reaction, such as when a rocket burns fuel during take off.  Size of...

2. Rate of reaction

Measuring rate This section aims to cover the following topics: Define chemical reaction rate Define rate expression Relative rates of reaction and stoichiometry ratio Change in concentration over time The rate of a chemical reaction can be thought of as the speed at...

3. Differential Rate Laws

Methods for determining order of reaction This section looks at how concentration affects reaction rate. You will learn how to determine the order of a reaction. Reactions are often categorized into first, second, third order, etc. and this information is useful for...

4. Integrated Rate Laws

Overview The differential rate law relates the change in concentration of a reactant over a specified time. In other words, it tells us about the overall rate of a reaction from the beginning to the end of the reaction and the rate law also tells us how the speed of a...

5. Mechanisms and Intermediates

Reaction mechanism Chemical reactions often take place in multiple steps and it’s not always obvious from looking at the chemical equation. For example, the decomposition of ozone: From the equation, it appears that O₃ decomposes to O₂ in one step. In reality,...

6. Reaction Coordinate Diagram

Given the following reaction, sketch a reaction coordinate graph. The reaction involves two steps, step 1 is the slowest step and step 2 is the fastest step. Indicate on the diagram the overall enthalpy change of the reaction, the reaction for the transitions states and intermediate states.

H2(g) + 2ICl(g) –> 2HCl(g) + I2(g)