3. Matter: Its Properties and Measurements

Matter

anything that has mass, occupies space and can be observed

light

not considered matter because it has no mass

substances

form of matter that has a definite (constant) composition and distinct properties

mixtures

a combination of two or more substances in which the substances retain their distinct identities.

mixtures

can be created and then separated by physical means into pure components without changing the identities of the components

elements

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

compounds

composed of atoms of two or more elements chemically united in fixed proportions.

compounds

can be separated only by chemical means into their pure components

solid

Particles are tightly packed, vibrating about a fixed position

liquid

Particles are tightly packed, but are far enough apart to slide over one another

gas

Particles are very far apart and move freely

plasma

a high-energy state where particles are electrically charged

BOSE-EINSTEIN CONDENSATE

a state of matter formed when a group of atoms is cooled to almost absolute zero (-273 °C or 0 Kelvin)

BOSE-EINSTEIN CONDENSATE

At this extremely low temperature, the atoms lose nearly all their energy and “condense” into a single quantum state,behaving as if they are one super-atom

Physical properties

variables that we can measure without changing the identity of the substance being observed

Mass

measured by comparing the object given and some standard, using a balance.

Density

a ratio of mass to volume.

Mass

the amount of matter in an object

Volume

the amount of space matter occupies

Density

mass per unit volume (how tightly particles are packed)

Luster

how a substance reflects light from its surface

Color

visible appearance

Odor

smell

Taste

flavor (though not always safe to test)

Texture

how it feels (smooth, rough, soft, hard)

State of matter

solid, liquid, gas, plasma, or BEC

Melting point

temperature at which a solid becomes liquid

Boiling point

temperature at which a liquid becomes gas

Solubility

ability to dissolve in another substance

Conductivity

ability to conduct heat or electricity

Malleability

ability to be hammered into sheets

Ductility

ability to be stretched into wires

Magnetism

attraction to magnets

Chemical properties

associated with the types of chemical changes that a substance undergoes

Flammability

ability of a substance to burn in the presence of oxygen

Reactivity with other substances

tendency to interact with other chemicals

Toxicity

ability of a substance to harm living organisms

pH (Acidity or Basicity)

ability to act as an acid or a base

Oxidation/Corrosion

reaction with oxygen or other elements leading to deterioration

Heat of Combustion

amount of heat released when a substance burns

Ability to decompose

breaking down into simpler substances when heated or exposed

Radioactivity

spontaneous emission of radiation from unstable atoms

Physical Change

a change in the form or appearance of matter without changing its composition

Chemical change

a change where matter forms one or more new substances with different properties

Formation of a Precipitate (Solid)

A solid forms when two liquids are mixed

measurement

quantitative observation

Qualitative

description and does not involve a number

English system

standard system of units used in the United States

Metric system

standard system of units used by most of the rest of the industrialized world

International System

In 1960, an international agreement set up a system of units (le Système International in French), or the SI system

le Système International

Meaning of SI system

Fundamental Quantities

basic quantities measured by direct method units assigned=fundamental units (MKS or CGS)

Derived Quantities

emanate or a result of the combination of fundamental quantities after a set of operations

Significant Figures

Scientists use this to determine how precise a measurement is

significant

Non-zero integers always count as _ figures

not significant

All zeros to the left of the first nonzero digit are _

Leading zeros

All zeros to the left of the first nonzero digit

Captive zeros

zeros between non-zero digits

significant

zeros between non-zero digits always count as _ figures

significant

zeros at the right end of the number are _ if the number contains a decimal point

Trailing zeros

zeros at the right end of the number

Scientific Notation

used to express very large or very small numbers

Accuracy

refers to the agreement of a particular value with the true value

Precision

refers to the degree of agreement among several measurements of the same quantity

Precision

reflects the reproducibility of a given type of measurement

Random error

means that a measurement has an equal probability of being high or low

indeterminate error

random error is also called as _

Random error

Errors that happen unpredictably due
to small, uncontrollable factors

Systematic error

occurs in the same direction each time. it is either always high or always low

determinate error

systematic error is also called as _

Systematic error

Errors that are consistent and repeatable, caused by faulty equipment, wrong calibration, or observer bias.

Dimensional Analysis or Unit Factor Method

method of converting one unit to another using conversion factors.