Lecture 1 Gen Chem for Engineers 01:160:159
Chemistry – the study of matter, its properties, the changes it undergoes, and the energy associated
with these changes.
Matter – anything that has mass and volume.
Composition (of matter) – the types and amounts of simpler substances that make up the matter.
Properties (both physical and chemical) – characteristics that give each substance a unique identity.
Physical Properties – Properties that a substance shows by itself, without interacting with other
Chemical Properties – properties that a substance shows as it interacts or transforms into other
Scientific knowledge – testable, reproducible, explanatory, predictive, and tentative (can change as new
discoveries are made).
1. Conducting a hypothesis (a tentative explanation of facts and observations).
2. Test the hypothesis by performing an experiment (measurement – collect data).
3. Hypothesis is revised, and the process continues based on the observations.
When the hypothesis successfully predicts what will happen, we designate it as a scientific law.
(Scientific Law – a mathematical description of what will happen.)
A Theory – A theory is an explanation of the (scientific) law.
(Example) Boyle’s Law(scientific law): PV=k
The Kinetic Molecular Theory (theory) is the best explanation for Boyle’s Law
* NO HYPOTHESIS OR THEORY can ever be proven completely true, they can only be disproven *
S.I. Based Units (System International)
Physical Quality Unit Name Unit Abbreviation
1. Mass Kilogram Kg
2. Length Meter m
3. Time Second s
4. Temperature Kelvin K
5. Electric Current Ampere A
6. Amount of Substance Mole mol
7. Luminous Intensity Cardela cd Lecture 1 Gen Chem for Engineers 01:160:159
Common Prefixes used with S.I. units
Prefix Prefix Word Conventional Notation Exponential
tera T Trillion 1,000,000,000,000 1 x 1012
giga G Billion 1,000,000,000 1 x 10
mega M Million 1,000,000 1 x 106
kilo k Thousand 1,000 1 x 103
hecto h Hundred 100