Chemistry Chapter 1
Chemistry
the study of the composition, structure, and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes
Organic Chemistry
the study of most carbon-containing compounds
Inorganic Chemistry
the study of non-organic substances, many of which have organic fragments bonded to metals (organometallics)
Physical Chemistry
the study of the properties and changes of matter and their relation to energy
Analytical Chemistry
the identification of the components and composition of materials
Biochemistry
the study of substances and processes occurring in living things
Theoretical Chemistry
the use of mathematics and computers to understand the principles behind observed chemical behavior and to design and predict the properties of new compounds
Chemical
any substance that has a definite composition
Basic research
carried out for the sake of increasing knowledge, such as how and why a specific reaction occurs and what the properties of a substance are
Applied research
carried out to solve a problem
Technological development
typically involves the production and use of products that improve our quality of life
Mass
measure of the amount of matter
Matter
anything that has mass and takes up space
Atom
smallest unit of an element that maintains the chemical identity of that element
Element
pure substance that cannot be broken down into simpler, stable substances and is made of one type of atom
Compound
substance that can be broken down into simple stable substances. Each compound is made from the atoms of two or more elements that are chemically bonded
Extensive properties
depend on the amount of matter that is present
Intensive properties
do not depend on the amount of matter present
Physical property
characteristic that can be observed or measured without changing the identity of the substance
Physical change
a change in a substance that does not involve a change in the identity of the substance
Change of state
a physical change of a substance from one state to another
Solid
has definite volume and definite shape
Liquid
has a definite volume but an indefinite shape
Gas
has neither definite volume nor definite shape
Plasma
high-temperature physical state of matter in which atoms lose most of their electrons, particles that make up atoms
Chemical property
relates to a substance’s ability to undergo changes that transform it into different substances
Chemical change or Chemical reaction
change in which one or more substances are converted into different substances
Reactants
the substances that react in a chemical change
Products
the substances that are formed by the chemical change
Mixture
blend of 2 or more kinds of matter, each of which retains its own identity and properties
Homogeneous
uniform in composition
Solutions
homogeneous mixtures
Heterogeneous
not uniform throughout
Pure substance
has a fixed composition and differs from a mixture in that every sample of a given pure substance has exactly the same characteristic properties and every sample of a given pure substance has exactly the same composition
Groups or Families
the vertical columns of the periodic table
Periods
the horizontal rows of elements in the periodic table
Metal
an element that is a good electrical conductor and a good heat conductor. It is malleable, ductile, and has high tensile strength
nonmetal
is an element that is a poor conductor of heat and electricity and is brittle
Metalloid
is an element that has some characteristics of metals and some characteristics of nonmetals. They are solid at room temperature. They tend to be less malleable than metals, but not as brittle as nonmetals. Some have a somewhat metallic luster. They tend to be semiconductors of electricity
Noble Gases
elements in group 18 of the periodic table and are generally not reactive. Elements of this group are gases at room temperature.
What is the difference between a compound and an element?
An element only has one atom, while a compound combines two atoms through chemical bonds.
Is H2O a compound or element?
compound
Is O2 a compound or element?
element
Is mass an extensive property or intensive property?
extensive
Is density an extensive property or an intensive property?
intensive
Is color an extensive or an intensive property?
intensive
Is conductivity an extensive or an intensive property?
intensive
Is volume an extensive or an intensive property?
extensive
Is freezing point an extensive or an intensive property?
intensive
Describe the difference between a chemical and a physical change
A physical change is a change in a substance that does not involve a change in the identity of the substance, while a chemical change is a change in which one or more substances are converted into different substances.
Physical or chemical? Hair curls when the humidity increases
P
Physical or chemical? Meat blackens when cooked too long on a barbecue
C
Physical or chemical? The steel in a car has rust spots
C
Physical or chemical? Alcohol burns forming carbon dioxide and water
C
Physical or chemical? Milk curdles if a few drops of vinegar are added
C
Physical or chemical? Salad dressing separates into layers after standing
P
Physical or chemical? Spilling acid on cotton jeans creates a hole in them
C
Physical or chemical? Dry ice gradually vaporizes
P
Physical or chemical? Sugar dissolves in water
P
Physical or chemical? Alka Seltzer neutralizes stomach acid
C
How do a solid, a liquid, and a gas differ?
Solid molecules are all connected and vibrate in place. Liquid molecules are close together but can move past one another. Gas molecules move very rapidly and are great distances apart.
What is the difference between a mixture and a pure substance?
A mixture is when 2 types of matter blend and each retain its own identity and properties. A pure substance has fixed composition and every sample has exactly the same characteristic properties and composition.
Is milk pure, homogeneous, or heterogeneous?
Heterogeneous
Is wood pure, homogeneous, or heterogeneous?
Heterogeneous
Is salad dressing pure, homogeneous, or heterogeneous?
Heterogeneous
Is steel pure, homogeneous, or heterogeneous?
Homogeneous
Is pond water pure, homogeneous, or heterogeneous?
Heterogeneous
Is air pure, homogeneous, or heterogeneous?
Homogenous
Is a teaspoon of sugar pure, homogeneous, or heterogeneous?
Pure
Is aluminum foil pure, homogeneous, or heterogeneous?
Pure
Is a bag of various colored marbles pure, homogeneous, or heterogeneous?
Heterogeneous
Is a teaspoon of sugar dissolved in water pure, homogeneous, or heterogeneous?
Homogeneous
Is beach sand pure, homogeneous, or heterogeneous?
Heterogenous
Is blood pure, homogeneous, or heterogeneous?
Heterogeneous
Which are classified as a solution?
Homogeneous ones= steel, air, and a teaspoon of sugar dissolved in water
What process would you use to separate a mixture of 3 liquids, all with different boiling points?
distillation
In the following chemical reaction, sodium + water -> hydrogen + sodium hydroxide, which are the reactants? What could be substituted for the arrow?
1. sodium and water 2. yields or forms