General Chemistry Notes

Flashcards for General Chemistry Lecture Notes

Chemistry

Study of the composition, structure, and properties of matter and of the reactions by which one form of matter may be produced from or converted into other forms.

Qualitative analysis

Separation and identification of what is present in a given sample.

Quantitative analysis

Determination of how much of a substance is present in a given sample.

Physical chemistry

Concerned with the structure of matter, energy changes, and the laws, principles, and theories that explain the transformation of one form of matter into another.

Organic chemistry

Deals with reactions of the compounds of carbon

Inorganic chemistry

Deals with the chemistry of elements other than carbon and its compounds.

Biochemistry

Concerned with the substances comprising living organism bacteria, plants, animals and human.

Matter

Anything that occupies space and has mass.

Pure Substances

Have fixed composition and distinct properties.

Elements

Substances that cannot be decomposed into simpler substances by chemical means.

Metals

Exhibit properties like luster, malleability and electrical conductivity.

Nonmetals

All other materials that exhibit properties opposite to those of metals.

Metalloids

Materials which exhibit some of the properties of metals and also some of the properties of nonmetals.

Compounds

Substances composed of two or more elements united chemically in definite proportions by mass.

Acids

Substances that increase the hydronium ion in water.

Bases

Substances that increase the hydroxide ions in water.

Salts

Substances produced when acids and bases are mixed.

Mixtures

Composed of two or more kinds of matter each substance retains its own identity and properties, thus, it can be separated by physical means.

Homogeneous mixture

Have uniform composition throughout. Solutions are classified under this group. Ex. vinegar, brine, syrup

Heterogeneous mixtures

Substances whose compositions, properties, and appearance differ throughout. Ex. sand in water, chocolate chip ice cream

Gas or vapor

A substance whose particles are far apart, it has no fixed volume or shape; it expands or contracts to assume the shape and volume of its container.

Liquid

A substance that has fixed volume and but do not have fixed shape; it tends to flow freely, thus, it assumes the shape of the container that it occupies.

Solid

A substance that has fixed volume and fixed shape; the particles are closely packed thus it is rigid and tends to resist any change in shape.

Physical Properties

Are those characteristics that do not involve a change in the chemical identity of the matter.

Chemical Properties

Are those characteristics associated with how one kind of matter transforms into another kind. Ex. rusting metal, burning fuel, milk turning sour

Physical change

Does not involve a change of one kind of matter into another, no change in the fixed composition of the substance. Ex. Phase changes such as - melting, evaporation or boiling, sublimation

Chemical change

Involves the transformations or change of one kind of matter into another; it results in the formation of a new substance with different properties.

Energy

It is defined as the capacity to do work, where work is the process of causing matter to move against an opposing force.

Potential energy

Possessed by matter by virtue of its positions, conditions or composition. Ex. water at the top of a waterfall possesses potential energy because of its position.

Kinetic energy

Possessed by matter because of its motion Ex. as water falls from the top of a waterfall, its potential energy because kinetic energy.

Law of Conservation of Mass and Energy

States that mass and energy are neither created nor destroyed. They are just transformed from one form to another.

Law of Conservation of Mass

Total mass of reactants = total mass of product.

Law of Conservation of Energy

Total energy before reaction = total energy after reaction

Exothermic

Where energy is liberated or given off, chemical energy is converted into heat energy.

Endothermic

Where energy is absorbed heat, light or Electrical energy is converted to chemical energy.

Law of Definite Proportion

States that "all sample of a pure composed contain some elements in a definite proportion by mass.

Law of Multiple Proportions

States that when two elements combine to form more than one compound, the different weights of one that combined with a fixed weight of other are in the ration of small whole numbers.

Periodic Table of Elements

Discovered it in the mid-nineteenth century, and it has been of immeasurable use in the development of chemistry. The order of elements in the periodic system is determined by their atomic numbers

J.A.R. Newlands

Suggested classifying the elements in order of increasing atomic weights in 1864, assigning ordinal numbers from unity upward to the elements and dividing them into seven groups with properties closely related to the first seven elements widely known: hydrogen, lithium, beryllium, boron, carbon, nitrogen, and oxygen.

Scientific Notation

Is a way of expressing number that are too big or too small to be conveniently written in decimal commonly used by scientist mathematicians and engineers.

Atomic Theory

Is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms

Dalton's Atomic Theory: 1

Elements are made of extremely small particles called atoms.

Dalton's Atomic Theory: 2

Atoms of a given element are identical in size, mass and other properties.

Dalton's Atomic Theory: 3

Atoms cannot be subdivided, created or destroyed.

Dalton's Atomic Theory: 4

Atoms are combined, separated or rearranged through chemical reactions.

Dalton's Atomic Theory: 5

Atoms of different elements combine in simple whole - number ratios to form chemical compounds

Atom

Smallest (unit) possible amount of matter which still retains its identity as a chemical element, consisting of a nucleus surrounded by electrons.

Proton

Positively charged subatomic particle forming part of the nucleus of an atom and determining the atomic number of an element. It weighs 1 atomic mass unit or amu.

Neutron

A subatomic particle forming part of the atom. It has no charge. It is equal in mass to a proton or it weighs 1 amu.

Electron

An electron is a subatomic particle with a negative charge. It can be either free (not bound to any atom) or tied to an atom's nucleus.