Chapters 1-2 Flashcards
Matter
Anything that has mass and occupies space
Chemistry
Study of the composition of matter and the changes it undergoes
Organic chemistry
The study of compounds containing carbon
Inorganic chemistry
Study of substances that do not contain carbon
Biochemistry
Focuses on processes that take place in organisms
Analytical chemistry
Focuses on the composition of matter
Physical chemistry
Deals with the mechanism, rate, and energy transfer that occurs when matter undergoes a change
Pure chemistry
Pursuit of chemical knowledge for its own sake
Applied chemistry
Research that is directed toward a practical goal or application
Big Ideas in Chemistry (8)
- Chemistry as central science
- Electrons and the structure of atoms
- Bonding and interactions
- Reactions
- Kinetic theory
- The mole and quantifying matter
- Matter and energy
- Carbon chemistry
Why is the scope of chemistry so vast?
It affects all aspects of life and most natural events because everything is made of matter.
Technology
The means by which a society provides it’s members with those things needed and desired
3 general reasons to study chemistry
- Explain the natural world
- Prepare people for career opportunities
- Produce informed citizens
Outcomes of modern research in chemistry
Technologies that benefit the environment, conserve and produce energy, improve human life, and expand our knowledge of the universe
How did Lavoisier help transform chemistry?
Transformed it from a science of observation to a science of measurement?
Steps in scientific method?
- Make an observation
- Form a hypothesis
- Test the hypothesis w/ an experiment
- Develop a theory
What role do collaboration and communication play in science?
Increase the likelihood of a successful outcome
Scientific method
A logical, systematic approach to solving a scientific problem
Observation
Information obtained through the senses; in science, often involves a measurement
Hypothesis
A proposed explanation for an observation
Experiment
A repeatable procedure, used to test a hypothesis
Independent variable
Variable that is changed during an experiment
Dependent variable
The variable that is observed during an experiment
Model
A representation of an object or event
Theory
A well-tested explanation for a broad set of observations
Scientific law
A concise statement that summarizes the results of many observations and experiments (doesn’t try to offer an explanation)
What are 3 states of matter?
Solid, liquid, gas
How can physical changes be classified?
Reversible (ex. freezing water can be reversed by melting it back) or irreversible (smashing a rock cannot be undone)
Mass
A measure of the amount of matter that an object contains; standard unit = kilogram
Volume
A measure of the space occupied by a sample of matter
Extensive property
Depends on the amount of matter in a sample (ex. mass, volume)
Intensive property
Depends on the type of matter in a sample (ex. color, texture)
Substance
Matter that has a uniform and definite composition; either an element or a compound
Physical property
Quality that can be observed/measured without changing the substance’s composition
Solid
Form of matter that has a definite shape or volume; molecules are packed together in a rigid formation
Liquid
Form of matter that flows, has a fixed volume, and an indefinite shape; particles are close together, but can flow past each other freely
Gas
Form of matter that takes the shape and volume of its container; no definite shape or volume; particles are relatively far apart and can move freely
Vapor
The gaseous state of a substance that is generally a liquid or solid at room temperature
Physical change
A change during which some properties of a material change, but the composition of the material does not change
How can mixtures be separated?
Differences in physical properties can be used to separate mixtures
Mixture
Physical blend of two or more substances that are not chemically combined
Heterogenous mixture
Is NOT uniform in composition; components are not evenly distributed throughout the mixture
Homogenous mixture
Is uniform in composition; components are evenly distributed and not easily distinguished; also known as a solution
Phase
Any part of a sample with uniform composition and properties; homogenous mixtures have one phase, heterogenous mixtures have multiple phases
Filtration
Separated a solid from the liquid in a heterogenous mixture
Distillation
Process used to separate components of a mixture using differences in boiling points
How can a substance and a mixture be distinguished?
If the composition is fixed, then it’s a substance. If the composition may vary, it’s a mixture.
Chemical formula
Used to represent a compound
Why is a periodic table useful?
Allows you to easily compare the properties of different elements
Element
Simplest form of matter that has a unique set of properties; cannot be broken down into simpler substances
Compound
Substance that contains 2 or more elements chemically combined in a fixed proportion
Chemical change
Produces matter with a different composition than the original matter
Chemical symbol
A 1 or 2 letter representation of an element
Periodic table
An arrangement of elements separated into groups based on a set of repeating properties
Period
Horizontal row in a periodic table
Group
Vertical column in a periodic table; elements in the same group have similar chemical and physical properties
What always happens during a chemical change?
The composition of matter always changes.
4 clues of a chemical change
- Transfer of energy
- Change in color
- Production of gas
- Formation of a precipitate
How are the mass of the reactants and the mass of the products in a chemical reaction related?
They are always equal.
Chemical property
Ability of a substance to undergo a specific chemical change
Chemical reaction
A change in which one or more reactants change into one or more products; bonds break in reactants, and bonds form in products
Reactant
Substance present at the start of a reaction
Product
Substance produced in a chemical reaction
Precipitate
A solid that forms and settles out of a liquid mixture
Law of conservation of mass
In any physical change or chemical reaction, mass is conserved; it can be neither created nor destroyed.
