Measurement of Heat Flow & Enthalpy Change

A calorimeter is a device used to measure the quantity of heat flow in a chemical reaction. Two of the most common types of calorimeters are...

Laws of Thermochemistry

Understanding Enthalpy and Thermochemical Equations Thermochemical equations are just like other balanced equations except they also specif...

Thermochemistry Table for Common Compounds

The molar heat of formation of a compound (ΔH f ) is equal to its enthalpy change (ΔH) when one mole of compound is formed at 25°C and 1 atm...

Cations and Anions in Aqueous Solution

These are molar heats of formation for anions and cations in aqueous solution. In all cases, the heats of formation are given in kJ/mol at 2...

Endothermic Reaction Demonstration

An endothermic process or reaction absorbs energy in the form of heat (endergonic processes or reactions absorb energy, not necessarily as h...

Paypal Gift Option

OK, I was originally concerned about the inability to create mailing lables if someone sent me funds via the recently added "gift"...

Hot Ice or Sodium Acetate

Sodium acetate or hot ice is an amazing chemical you can prepare yourself from baking soda and vinegar. You can cool a solution of sodium a...

Create an Exothermic Chemical Reaction

Exothermic chemical reactions produce heat. In this reaction vinegar is used to remove the protective coating from steel wool, allowing it ...

Endothermic and Exothermic Reactions

Many chemical reactions release energy in the form of heat, light, or sound. These are exothermic reactions. Exothermic reactions may occur ...

Endothermic Chemical Reaction

Most endothermic reactions contain toxic chemicals, but this reaction is safe and easy. Use it as a demonstration or vary the amounts of cit...

Heat of Formation Worked Example Problem

1. Heat of Formation Problem Calculate ΔH for the following reaction: 8 Al(s) + 3 Fe 3 O 4 (s) --> 4 Al 2 O 3 (s) + 9 Fe(s) Heat of ...

Enthalpy Change Example Problem

Problem Hydrogen peroxide decomposes according to the following thermochemical reaction: H 2 O 2 (l) → H 2 O(l) + 1/2 O 2 (g); ΔH = -98.2 kJ...

Bond Energies and Enthalpy Change Example Chemistry Problem

Problem Estimate the change in enthalpy, ΔH, for the following reaction: H 2 (g) + Cl 2 (g) → 2 HCl (g) Solution To work this problem...

Standard State Conditions - Standard Temperature and Pressure

Values of thermodynamic quantities are commonly expressed for standard state conditions, so it is a good idea to understand what the standar...

Laws of Thermochemistry

Thermochemical equations are just like other balanced equations except they also specify the heat flow for the reaction. The heat flow is l...

Polynucleotides

Biopolymers IV Polynucleotides Introduction Polynucleotides, which are more often called nucleic acids, are polymeric glycosylamines ...

Polypeptides

Biopolymers III Polypeptides Introduction One of the most common reactions of carboxylic acids and related compounds is nucleophili...

Polysaccharides

Biopolymers II Polysaccharides Introduction By far the most important polysaccharides are polymers of D-glucos...

Condensation Polymers

Polymers and Plastics II Introduction One of the characteristic reactions of carboxylic acids is esterification , a process that involve...