CH 1.1-1.6 Flashcards
Molecule
Collection of atoms
STM
Scanning tunneling microscope; microscope that allows us to see atoms
2 fundamental concepts of chemistry
- Matter is composed of various types of atoms
- One substance changes to another by reorganizing the way the atoms are attached to each other
Scientific Method
- The basis on which a scientific enquiry is conducted.
1. Making observations (collecting data)
2. Suggesting a possible explanation (formulating a hypothesis)
3. Doing experiments to test the possible explanation (testing the hypothesis)
Qualitative observation
Descriptive observation
Quantitative observation
Measured observation, includes both a number and a unit
Theory
Aka model; a set of tested hypotheses that gives an overall EXPLANATION of some natural phenomenon; an interpretation
- a human invention
Observation
Something that is witnessed and can be recorded
Natural law
A statement that expresses generally observed behavior; SUMMARY of observed behavior
- A consistent set of observations that applies to many different systems
Law of Conservation of Mass
Mass is neither created nor destroyed
Robert Boyle
- 1st “chemist” to perform truly quantitative experiments
- measured the relationship between the pressure & volume of air
- The Skeptical Chymist
- Believed that an element is anything that cannot be betoken down into simpler substances
- Believed all theories must be proved experimentally before being regarded as true
Joseph Priestley
English clergyman & scientist that discovered oxygen gas by heating mercury oxide in a closed environment
- Gas was found to support light and burning
Antoine Lavoisier
French chemist that explained the true nature of combustion
- coined the Law of Conservation of Mass
- Discovered that life was supported by a process that involved oxygen (founded the correct name for oxygen)
- Elementary Treatise on Chemisty
- Wrote the 1st modern chemistry textbook
- Father of Modern Chemistry
- Found that heating lead sample makes it heavier while overall weight of sealed glass jar remained constant
Joseph Proust
Lavoisier’s student that coined the Law of Definite Proportion
Law of Definite Proportion
A given compound always contains exactly the same proportion of elements by mass
- Aka the Law of Constant Composition by Mass
John Dalton
Discovered that compounds are made of atoms & a given pair of atoms can form a variety of compounds
- Father of Atomic theory
Science
Study in which humans attempt to explain knowledge about themselves and their surroundings
Experimentation
Process that is used to explore repeatable and consistent observations and answer questions
Law
A concise, verbal statement that SUMMARIZES facts about a natural phenomenon
- Series of experiments that are consistent
- Doesn’t change
Measurement
Quantitative observation consisting of a number & a scale
Accuracy
agreement of a measurement (or a set of observations) with the true value
Precision
degree of agreement among several measurements of the same quantity, or the repeatability of a measurement
Error
the difference btwn the true value & measured value
Random/Indeterminate errors
Affect precision of measurement. Causes data to be more scattered around an average value
- Improved w/ instrument
Systematic/Determinate errors
Affect the accuracy of a result. Causes average of a set of data to differ from the true value.
- You can control
- Improve through technique
1 pound = … grams
454
1 inch = … cm
2.54
1 quart = … L
0.946
Tc –> Tk
Tc + 273.15
Tk –> Tc
Tk - 273.15
Tf –> Tc
(Tf - 32) x 5/9
Tc –> Tf
Tc x 9/5 + 32
Density formula
Mass/volume