How To: Weigh samples in the lab using a balance

The Interactive Lab Primer (ILP) has been developed as part of the Royal Society of Chemistry Teacher Fellowship Scheme, one of the themes of the Chemistry for Our Future program, and initiative which aims to secure a strong and sustainable future for the chemical sciences in higher education. The aim of the ILP is to address the diverse range of experience and skills students bring with them to a university by offering a resource to support their transition from school to the university chemistry laboratory. The ILP is quite simply a visual guide to common laboratory techniques.

This video tutorial will teach you how to weigh samples in the lab using a balance. Weighing is done to ensure the correct amount of a reactant is added to a reaction, for the preparation of standard solutions or the weighing of a product to calculate a yield. There is also a branch of analytical chemistry called 'Gravimetric Analysis' where precipitates are accurately weighed as a means to determine concentrations.

Always make yourself aware of the hazards associated with the chemicals involved in a practical before you even start. If you ever come across a chemical you do not know the hazard of you must assume that is very hazardous until you find otherwise.