Module 1 & 2 Flashcards
chemistry is
the study of matter, its chemical and physical properties, the chemical and physical changes it undergoes, and the energy changes that accompany those processes
matter is
anything that has mass and occupies space
matter gains and loses ____ as it undergoes ___
energy; change
The scientific method is
a systematic approach to the discovery of new information
Characteristics of the scientific method include:
observation of a phenomenon; formulation of a question concerning the observation; presentation of a hypothesis; experimentation, with the collection and analysis of data and results in an attempt to support or disprove a hypothesis; ultimate goal of process is to form a theory supported by extensive testing
a scientific law is
the summary of a large quantity of information supporting a theory or hypothesis
pure substances of matter can be subdivided into what two groups?
elements or compounds
mixtures can be subdivided into what two groups?
homogeneous mixtures or heterogeneous mixtures
properties of matter can be classified as what two things?
physical property and chemical property
a physical property is
observed without changing the composition of matter
a chemical property is
observed as the matter is converted to a new substance
properties can be classified into what two categories?
intensive and extensive
intensive property is
a property that does not depend on the quantity of matter
extensive property is
a property that does depend on the quantity of matter
Why does the metric system have a advantage over the English system?
metric units are systematically related to each other by powers of ten
mass is…
a measure of the quantity of matter
Weight is
the force of gravity on an object
the metric unit for mass is ____; a common English mass unit is the ____
gram; pound
length is
the distance between two points
volume is
the space occupied by an object
the metric unit of time is the___
second
significant figures are
all digits in a measurement known with certainty plus one uncertain digit
what is scientific notation?
a way to express a number as a power of ten
temperature is
the degree of hotness of an object
energy is
the ability to do work
energy is categorized as ___ energy and ____ energy
kinetic and potential
concentration is
a measure of the amount of a substance contained in a specified amount of a mixture
density is
the ratio of mass to volume and is an intensive property; typically reported as g/mL or g/cm3
specific gravity is
the ratio of the density of an object to the density of pure water at 4 degrees C; numerically equal to density but without units
What are the 6 postulates of Daltons atomic theory?
all matter consists of tiny particles called atoms; an atom cannot be created, divided, destroyed, or converted to any other type of atom; atoms of a particular element have identical properties; atoms of different elements have different properties; atoms of different elements combine in simple whole-number ratios to produce compounds (stable combinations of atoms);
spectroscopy
information obtained from the absorption or emission of light by atoms that yield valuable insight into structure of an atom
electromagnetic radiation travels in ___ from a source; the most recognizable source is the ___
waves; sun
the speed of light is notated as
3.0 x 10-to-the-8th power m/s
electromagnetic spectrum
a collection of all electromagnetic radiation, including each of the different wavelengths
what is electron density?
the proportion (density) to the probability of finding the electron at any point in time
the periodic law is…
embodied by Mendeleev’s statement which states “the elements, if arranged according to their atomic weights (masses), show a distinct periodicity (regular variation) of their properties”
Describe a common property of metals? Nonmetals?
Metals tend to lose electrons while nonmetal tend to gain them
What are principal energy levels?
regions where electrons may be found and in which integral values are designated n = 1, n = 2, n=3, etc.; related to the average distance from the nucleus; n = 1 level is the closest to the nucleus
The maximum number of electrons that a principal energy level can hold is equal to what?
2(n) to the 2nd power
Only one ___ orbital can be found in any ___ orbital
s; n
Which orbitals are important in determining the properties of the transition metals?
d orbitals
what are paired electrons?
two electrons in one orbital that possess opposite spins ; their number and arrangement within an atom are responsible for magnetic properties of elements
no more than __ electrons can be placed in any orbital; each principle energy level (n) can contain only ___ subshells
2; n
what is the aufbau principle?
electrons fill the lowest energy orbital that is available
What is the electron capacity of the s orbital? p? d?
2; 6; 10
what is isoelectric?
an ion that has the same electron configuration as its nearest noble gas, making it stable
Transition and representative metals tend to form ___ by losing electrons
cation
nonmetallic elements tend to form ___ by gain electrons
anions
what is electron affinity?
the potential to gain electrons, or the energy change when a single electron is added to an isolated atom; large electron affinity mans a large release of energy indicating more electrons equal a more stable atom
ionization energy is
the energy required to remove an electron from an isolated atom; decreases down a group; increases across a period; highest for noble gases
electron affinities generally ___ down a ___ and ___ across a ____
decrease; group; increase; period
Which of the following properties of matter is not considered to be an intensive property but rather is best understood as an extensive property?
mass
What are the correct expressions when the following numbers are put into scientific notation? 113.7789; 0.0003885; 5.229
1.137789 x 102and 3.885 x 10-4and 5.229
Which of the following atoms or ions does not contain a full octet of electrons in its outmost energy level? Magnesium is in Group IIA; sulfur is in Group VIA; bromine is in Group VIIA; Argon is in Group VIIIA.
S
Which of the following is the correct electron configuration for a neutral atom of chlorine (Cl), atomic number 17? Chlorine is located in Group VIIA and period 3 of the periodic table.
1s2, 2s2, 2p6, 3s2, 3p5
Which of the following elements is not classified as a metal in the periodic table?
selenium
