Stoichiometry, Formulas and Equations
From ZuluNotes - Free Leaving Cert Notes
This is quite a broad section which deals with states of matter, gas laws, the mole, chemical formulae and chemical equations.[1] Much of these topics are mathematical with very little theory to be learnt. Despite this, knowing the principles behind each calculation can help you understand and manipulate formulae.
Contents |
The Mole
Strictly speaking, a mole is the amount of a substance that contains the Avogadro Constant number of particles. For this course [2] you must know about:
- The Avogadro Constant
- The mole and the relevant calculations
- Standard temperature and pressure
- Relative molecular mass / relative atomic mass
- Mandatory Experiment: To determine the relative molecular mass of a volatile liquid.
Gases
Main article: Gases
A gas is a substance possessing perfect molecular mobility and the property of indefinite expansion, as opposed to a solid or liquid.[3] For the course you need to be familiar with:
- Boyle's Law
- Boyle's Air Pump
- Charles' Law
- Combined Gas Law
- Motion of particles in various states of matter
- Diffusion
While Boyle's Law is given in the new leabhrán foirmlí agus táblaí (formulae and tables booklet), you still need to be able to apply it to calculations.
Stoichiometry
A mathematical mind goes a long way in this area, with almost all the questions based on maths. You need to know about:
- Empirical and molecular formulae and their related calculations.
- Percentage composition by mass and calculations.
- Structural formulae (simple examples).
- Balancing simple chemical equations.
- Calculations based on balanced equations using the mole concept (involving masses and volumes).
References
- ↑ http://www.education.ie/servlet/blobservlet/lc_chemistry_sy.pdf
- ↑ http://www.curriculumonline.ie/uploadedfiles/PDF/lc_chemistry_sy.pdf
- ↑ http://dictionary.reference.com/browse/gas
