Unit 1: Intro to Chemistry

Pure substance

Pure substance

Matter that has a uniform and unchanging composition

Physical property

A characteristic that can be observed or measured without changing the chemical’s composition

Examples of physical properties

Density, taste, color, odor, hardness, melting point, boiling point

Extensive Properties

dependent upon the amount of substance present.

Intensive Properties

independent of the amount of substance present.

Chemical property

The ability of a substance to combine with or change into one or more other substances

Chemical property examples

Rusting, inability of a substance to change into another

States of matter (definition)

all matter that exists on Earth

States of matter (list)

solid, liquid, gas

Solid

Form of matter that has it’s own definite shape and volume

Liquid

Form of matter that flows, has constant volume, and takes the shape of it’s container

Gas

Form of matter that conforms and fills the volume of it’s container

Vapor

Gas state of a solid or liquid

Physical changes

A change that occurs without altering the chemical makeup

Chemical change

A process that involves one or more substances changing into new substances

Law of conservation of mass

mass is neither created nor destroyed during a chemical reaction—it is conserved.

Mixture

combination of two or more pure substances in which each pure substance retains its individual chemical properties.

Heterogenous mixture

one that does not blend smoothly throughout and in which the individual substances remain distinct.

Homogenous mixture

constant composition throughout; it always has a single phase.

Solution

Also known as a homogenous mixture

Filtration

a technique that uses a porous barrier to separate a solid from a liquid.

Distillation

a separation technique that is based on differences in the boiling points of the substances involved.

Crystallization

a separation technique that results in the formation of pure solid particles of a substance from a solution containing the dissolved substance.

Chromatography

a technique that separates the components of a mixture (called the mobile phase) on the basis of the tendency of each to travel or be drawn across the surface of another material (called the stationary phase).

Element

a pure substance that cannot be separated into simpler substances by physical or chemical means.

Periodic table

organizes the elements into a grid of horizontal rows called periods and vertical columns called groups or families.

Compound

a combination of two or more different elements that are combined chemically.

Law of Definite Proportions

the elements comprising them combine in definite proportions by mass.

Percent by Mass

(Mass of Solute / Mass of Solution) × 100

Law of Multiple Proportions

when different compounds are formed by a combination of the same elements, different masses of one element combine with the same relative mass of the other element in a ratio of small whole numbers.

Decantation

Decantation is a process for the separation of mixtures of immiscible liquids or of a liquid and a solid mixture such as a suspension.

Sedimentation

Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier.

Distillation

The process of separating components of a mixture based on different boiling points

Simple Distillation

when the ingredients of the liquid mixture have changes of the boiling point close to

Fractional Distillation

used for mixtures that have closer boiling points.

Crystallization

Crystallization is a technique used for the purification of substances. A separation technique to separate solids from a solution.

Chromatography

a technique that separates the components of a mixture (called the mobile phase) based on the tendency of each to travel or be drawn across the surface of another material (called the stationary phase).

Sublimation

Sublimation is the separation technique where a substance makes a transition from the solid to the gas state directly.

Extraction

Extraction is the first step to separate the desired natural products from the raw materials.

Magnetic Separation

the process of separating components of mixtures by using a magnet to attract magnetic substances.

Measurement

A Type of observation

Qualitative Measurements

Descriptive Measurements

Quantitative measurements

Measures amount

Accuracy

How close the measurements are close to the accepted value

Precision

How close measurements are to each other

Scientific Notation

Short hand for writing very large or small numbers

Chemistry

The study of matter and the changes matter undergoes

Matter

Anything that has mass and occupies space

Chemistry areas of study

organic chemistry, inorganic chemistry, biochemistry, analytical chemistry, physical chemistry

Organic Chemistry

Study of all chemicals that contain carbon

Inorganic chemistry

Study of all chemicals that do not contain carbon

Biochemistry

Study of processes that take place in organisms

Analytical chemistry

Focuses on the composition of matter

Physical Chemistry

Deals with the mechanism, rate, energy transfer that occurs when matter undergoes a change.

Pure Chemistry

The pursuit of chemistry for its own sake (no commercial use)

Applied chemistry

Chemistry intended for other people