Exam 1 Vocab, Chem 101, BHC

Anything that possesses mass & occupies volume
The types & amounts of simpler substances that make up a sample of matter
Characteristics that give a substance its unique identity
Physical Property
A characteristic shown by a substance itself, without interacting with or changing into other substances
Physical Change
A change in which the physical form (or state) of a substance, but not its composition, is altered
Chemical Property
A characteristic of a substance that appears as it interacts with, or transforms into other substances
States of Matter
-Fixed shape

-Does not conform to container

States of Matter
-Fills a container to the extent of its own volume, thus forming a surface
States of Matter
-Fills its container regardless of the shape because its particles are far apart
Chemical Change
A change in which one or more substances are converted into one or more substances with different composition & properties
The capacity to do work, that is, to move matter
Kinetic Energy
Energy an object has because it is in motion
Potential Energy
Energy an object has because of its position in relation to other objects or because of its composition
A fact obtained with the senses, often with the aid of instruments. Quantitative observations provide data that can be compared.
Pieces of quantitative information obtained by observation
Natural Law
A summary, often in mathematical form, of a universal observation
A testable proposal made to explain an observation. If inconsistent with experimental results, a hypothesis is revised or discarded
A set of procedural steps that tests a hypothesis
Theory (Model)
A simplified conceptual picture based on experiment that explains how a natural phenomenon occurs
The simplest type of substance with unique physical & chemical properties. An element consists of only one kind of atom, so it cannot be broken down into simpler substances.
A type of matter, either an element or a compound, that has a fixed composition
A structure consisting of two or more atoms that are bound chemically & behave as an independent unit
A substance composed of two or more elements that are chemically combined in fixed proportions
A group of two or more elements &/or compounds that are physically intermingled
The smallest particle of an element that retains the chemical nature of the element.

A neutral, spherical entity composed of a positively charged central nucleus surrounded by one or more negatively charged electrons

A subatomic particle found in the nucleus that has a unit positive charge
An uncharged subatomic particle found in the nucleus, with a mass slightly greater than that of a proton
A subatomic particle that possesses a unit negative charge & occupies the space around the atomic nucleus
Mass Number (A)
The total number of protons & neutrons in the nucleus of an atom
Atomic Mass
The average of the masses of the naturally occurring isotopes of an element weighted according to their abundances
Horizontal rows on the periodic table
Vertical columns in the periodic table

Elements in a group usually have the same outer electron configuration and, thus, similar chemical behavior

Transition Element
An element that occupies the d block of the periodic table.

One whose d orbitals are being filled

A substance or mixture that is relatively shiny & malleable & is a good conductor of heat & electricity.

In reactions, metals tend to transfer electrons to nonmetals & form ionic compounds.

An element that lacks metallic properties.

In reactions, nonmetals tend to share electrons with each other to form covalent compounds or accept electrons from metals to form ionic compounds

An element with properties between those of metals and nonmetals
Alkali Metal
An element with some properties that are unique for metals: unusually soft & can be easily cut with a knife, lower melting & boiling points than any other group of metals, & lower densities than most metals. Highly reactive

Group 1A(1) [Except Hydrogen]

Alkaline Earth Metals
An element whose oxides give basic (alkaline) solutions & melt at such high temperatures that they remained as solids (“earths”) in alchemist’s fires. Soft & lightweight, but stronger metallic bonding & smaller atomic sizes make them harder & denser than the alkali metals. Highly reactive

Group 2A(2)

Highly reactive nonmetals

Group 7A(17)

Noble Gases
Relatively unreactive nonmetals

Group 8A(18)

Oxygen Family
Group 6A(16)

Other main groups [3A(13) to 6A(16)] are often named after the first element in the group.

Ionic compounds
Combination of elements formed by transferring electrons from one element to another
Covalent Compounds
Combination of elements formed by sharing electrons between atoms of different elements
Binary Ionic Compound
The simplest type of ionic compound, composed of two elements, that typically forms when a metal reacts with a nonmetal.

Metal atom loses one or more electrons (cation +) and nonmetal atom gains one or more electrons (anion -)

A positively charged ion
A negatively charged ion
Monatomic ion
A cation or anion derived from a single atom
Covalent Bond
A pair of electrons mutually attracted by the two nuclei
Polyatomic Ion
Consist of two or more atoms bonded covalently and have a net positive or negative charge
Law of Mass Conservation
A mass law stating that the total mass of substances does not change during a chemical reaction
Law of Definite Composition
A mass law stating that, no matter what its source, a particular compound is composed of the same elements in the same parts (fractions) by mass
Law of Multiple Proportions
A mass law stating that if elements A and B react to form two or more compounds, the different masses of B that combine with a fixed mass of A can be expressed as a ratio of small whole numbers
Atoms of a give atomic number (that is, of a specific element) that have different numbers of neutrons and therefore different mass numbers.
Isotopic Mass
The mass (in amu) of an isotope relative to the mass of carbon-12
Atomic Mass Unit (amu)
A mass exactly equal to 1/12 the mass of a carbon-12 atom

Also called dalton, Da