General Chemistry

Chemistry

Branch of science that deals with the study of matter

Study of chemical substances that contains carbon-carbon bonds

Organic chem examples

STudy of substances that do not contain carbon-carbon bonds

Examples of inroganic chem

Examples of physical chem

deals with the behavior and changes of matter and related energy changes

Study of different components and composition of substances

Example of Analytical chem

Biochemistry examples

Study of matter and processes in living organisms

Scientific method

process of defining a problem, making experiments, collecting data, interpreting the data, formulating a hypothesis, and summarizing the data in a way that is simple and precise.

experiment

Any test or trial that is used to collect information or data to answer a specific set of questions or inquiries.

It is a systematic approach to research used in almost all types of engineering sciences.

This is the way scientists, chemists, physicists and biologists study everything around them.

Data

Raw information collected from the experiments. Once the data are organized, they are now referred to as results

conclusions

If one makes deductions from the results, they are now referred to as

Qualitative Data

It is the general statements about one's observation on the system. Examples: color, odor, shapе

Quantitative Data

It refers to the numbers obtained by measuring certain parameters of the system. Example: mass, length, volume

Hypothesis

statement produced out of few observations without much experimental evidence.

It is a possible explanation for what has been observed

Law

statement produced out of thorough research and experimentation that indicates the relationships between different phenomena that is always the same under the same conditions (e.g. Newton's Law of Motions, Ideal Gas Law etc.). Scientific laws stand the test of time.

Theory

It is a unifying principle that explains a body of facts and/or those laws that are based on them (e.g. Big Bang Theory).
Theories can be proved or disproved in new experiments.

Model

visual, verbal, or mathematical explanation of experimental resutts that is only accurate under certain conditions and in certain environments. Unlike scientific laws, models are not universal``

Matter

anything that has mass and occupies space.

Pure Substance

Matter that can be physically separated

Mixture

Matter that cannot be physically separated

Homogenous

Uniform composition mixture

Heterogenous

Non-uniform composition mixture

Compound

Can be chemically decomposed pure substance

Element

Cannot be chemically decomposed pure substance

Mass

measurement of the amount of matter in a certain object.

Solid

Molecules of matter at this state are closely held together in an orderly sequence such that they are not free to move.

Rigid and are almost incompressible.

Liquid

Molecules of matter at this state are farther apart compared to molecules of solid.
Can flow and it follows the shape of its container. Like solids, they are hard to compress.

Gas

Molecules of matter at this state are separated by large distances relative to the size of the molecules. Hence, molecules are free to move randomly in different directions.
Can flow and are easier to compress compared to solids and liquids.
They follow the volume and the shape of their containers.

fluids

substances that can flow
liquids and gases are classified as this

ionization

gas to plasma

plasma to gas

deionization

deposition

gas to solid

solid to gas

sublimation

heat

matter can be transformed from one form to another, and this will involve the transfer of energy in the form of

Plasma

Similar to gases except that it is made up of free electrons and ions from the element.

For instance, neon signs are glass tubes filled with gas. When electricity flows through the tube (e.g. the light is turned on), the electricity charges the gas and creates this inside the tube

Bose-Einstein Condensate (BEC)

The newest state of matter as it was discovered only in 1995 by Cornell and Weiman, although Satyendra Bose and Albert Einstein predicted this state of matter in the 1920's.
It is the opposite of plasma so this state of matter must be supercooled and will occur a few billionths temperature within the absolute zero tempera ture.

Physical properties

These are properties that can be observed or measured without changing the composition of the original substance being studied. Examples: Mass, color, odor, size, density, freezing point, boiling point, etc.

Chemical properties

These are properties that can be observed or measured after changing chemically the substance being studied. Examples: Conductivity malleability, reactivity, flammability, toxicity, radioactivity, oxidation, etc.

Extensive properties

These are properties that depend on the amount or on the "extent" of substance or matter being studied;

Additive which means that more matter equates to a higher value of the property.
Examples: Mass, volume, length, width, weight, area, energy, etc.

Intensive properties

These are properties that are independent on the amount of substance or matter being studied;
not additive which means that regardless of the amount of substance, these properties have a fixed value.
Examples: Color, density, temperature, pressure, boiling point, melting point, freezing point, etc.

pure substance

a matter that has definite composition and properties.
It cannot be separated into two or more substances by physical means. Examples: silver, gold, oxygen, water, salt, ammonia, etc.

element

pure substance that cannot be broken down into a much simpler substance by chemical means.
symbolized by one or two letters in which the first letter is always capitalized.

compound

combination of two or more elements chemically combined in fixed proportions. It can be separated by chemical means into its respective components.

mixture

composed of different substances that do not have constant composition.

can be separated into different substances by physical means without changing the identities of the components.

Examples: air, coffee, cement, etc.

Colloids

mixtures in which the particles do not settle at the bottom upon standing.

Suspensions

mixtures in which the particles settle at the bottom upon standing.

Decantation or Floatation

process of separating large solid particles from liquids by allowing the liquid to flow white the large solid particles settle.

Filtration

process of separating small solid particles from liquid by passing the mixture through a porous medium

Distillation

process of separating the liquid by boiling the mixture to vaporize the liquid and then cooling the vapor to condense it

Fractional distillation

process of separating liquid mixtures whose component substances have narrow differences in boiling point

Steam distillation

process of separating volatile oils from plants

Mechanical separation

process involving the use of tools such as forceps, sleves, etc.

Centrifugation

process that speeds up the settling of the precipitates using a centrifuge which is a motor-driven apparatus
separate substances of different densities

Chromatography

process of using the difference in degree to which the substances are absorbed on the surface of an inert substance.

Solvent extraction

process of separating the mixture to its component substances by making use of the difference in solubility of the substances.

Amalgation

process of extracting gold from its ore

Cyanidation

process of extracting gold from its ore by using cyanide.

Measurement

important in engineering science as it allows properties to be defined in a quantitative value.

Some typical devices used in chemistry are flasks, pipes, and graduated cytinders.

Macroscopic properties

properties that can be measured directly

microscopic properties

can be measured using an indirect method

St system (Systeme Internationale d' Unites or the International System of Units)

the revised metric system of units proposed by the General Conference of Weights and Measures in 1960. it has 7 base units, and all other units can be derived from these base units.

decimal system

The SI system is based on this system

SI unit of Mass

kg

SI unit of length

m

SI unit of time

s

SI unit of temp

K

SI unit of electric current

A

SI unit of amount of substance

mol

SI unit of luminous intensity

Cd - candela

Giga

10^9

Mega

10^6

Kilo

10³

Deci

10^-1

Centi

10^-2

Milli

10^-3

Micro

10^-6

Nano

10^-9

Pico

10^-12

Meter

usually defined at 10^-7 of the distance from the equator to the North Pole along a meridian passing Paris, France.
It is also defined as the distance between two parallel marks in a specially made platinum-iridium bat.

kilogram

mass of a specially made Cylinder of platinum-iridium

Significant figures or significant digits

meaningful digits in a measurement. It is usually impossible to get the exact value of a quantity being measured, hence it is important to indicate the margin of error by indicating which digits are significant.

Significant figures according to the rules

Non-zero digits

Zero btwn non-zero digits

If a number is greater than 1, all zeroes after the decimal point
If a number is less than 1, zeroes that are after and between the non-zero digits

Non-significant figures according to the rules

Zeroes to the left of the first non-zero digit

degree of accuracy

measurements are close to the exact value

degree of precision

consistency of the measurements.

Accurate measurements

usually precise