Chapter 1: Matter and Change

Section 1: Chemistry is a Physical Science What is Chemistry? It is the study of the composition, structure, and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes. What is a Chemical? Any substance that has a definite composition. Examples: Sucrose, Carbon Dioxide, and Water Knowing the composition allows us to find a suitable use for them. What is a material’s makeup? How does a material change when heated, cooled, or mixed with other materials? Why does this behavior occur?

Branches of Chemistry Organic Chemistry: study of carbon-containing compounds. Inorganic Chemistry: study of non-organic compounds. Physical Chemistry: study of the properties and changes of matter and their relation to energy.

Branches of Chemistry, Cont. Analytical Chemistry: the identification of the components and composition of materials. Biochemistry: study of substances and processes occurring in living things. Theoretical Chemistry: use of mathematics and computers to understand the principles behind observed chemical behavior and to design and predict the properties of new compounds.

Types of Research Basic Research Applied Research Carried out for the sake of increasing knowledge. 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 Involves the production and use of products that improve our quality of life.

Section 2: Matter and Its Properties Matter: is anything that has mass and takes up space. Not everything is made up of matter Ex. Heat, Gravity, Light, Sound Matter has many different forms

Basic Building Blocks of Matter Matter comes in many forms and the building blocks are atoms and molecules. Atoms are the units for elements. Molecules are the unit for compounds which are made up of atoms of elements. Ex. Water 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 up of one type of atom. Compound: substance that can be broken down into simple substances. Made from the atoms of two or more elements that are chemically bonded. Molecule: compounds are made up of molecules. Water is a compound and is made up of individual water molecules which are made up of atoms of elements. Hydrogen and Oxygen.

Mass and Weight Mass: is a measurement of the amount of matter Weight: is a measure not only of the amount of matter but also of the effect of Earth’s gravitational pull on that matter Scientist use mass instead of weight because it is a way to measure matter independent of gravitational force. Volume: amount of 3D space an object occupies

Properties and Changes in Matter Properties are characteristics that define an entire set of substances and can help to reveal the identity of an unknown substance. Extensive Properties: depend on the amount of matter present Ex. Volume, Mass, and Amount of Energy Intensive Properties: do not depend on the amount of matter present. Ex. Melting Point, Boiling Point, and Density

Physical Properties Physical Properties Ex. Melting Point and Boiling Point Physical Change aka Change of State Ex. Grinding, Cutting, Melting, or Boiling a substance There are 4 states of matter Solid, Liquid, Gas, and Plasma - Ex. Found in fluorescent light bulbs

Chemical Properties and Energy Ex. Ability of charcoal to burn, Iron to rust Chemical Change aka Chemical Reaction Energy is always involved in chemical and physical changes and can take different forms such as light or heat. Law of Conservation of Energy: Energy can be released or absorbed in a change, it is not created or destroyed.

Chemical Reactions Involves Reactants and Products The burning of charcoal is a chemical reaction. Carbon + Oxygen  Carbon Dioxide Reactants Product

Section 3 Elements 13

Why is the Periodic Table important to me? You get to use it on every test. It organizes lots of information about all the known elements. 14

Dmitri Mendeleev: Father of the Periodic Table In 1869 he published a table of the elements. 1834 - 1907 16

Dmitri Mendeleev SOME PROBLEMS… He left blank spaces for what he said were undiscovered elements. (Turned out he was right!) He broke the pattern of increasing atomic weight to keep similar reacting elements together. Corrected masses of some elements. HOW HIS WORKED… 70 known elements. Put elements in rows by increasing atomic weight. Put elements in columns by their properties. 17

After the discovery between 1874 and 1885, and the fact that Mendeleev’s predictions for Sc, Ga, and Ge were amazingly close to the actual values, his table was generally accepted. 18

The Current Periodic Table Mendeleev wasn’t too far off. Now the elements are put in rows by increasing ATOMIC NUMBER!! Elements in the same group have similar chemical and physical properties!! (Mendeleev did that on purpose.) 19

Groups: The vertical columns of the periodic table Groups: The vertical columns of the periodic table. Also called families. Periods: The horizontal rows of the periodic table.

3 classes of elements left malleable ductile conductors shiny surface 1. Metals: located to the _______ of the dark zig-zag line Properties of Metals All Solids!!! Except one – who is it?? shiny surface ______________ (you can pound it into a flat sheet) ______________ (you can draw it into a thin wire) good _______________ (heat/electricity travels through it easily) left malleable ductile conductors 21

Properties of Nonmetals right 2. Nonmetals: located to the ___________ of the dark zig-zag line. Properties of Nonmetals _______ surface ______________ good _______________ (or poor conductors) dull brittle sulfur insulators 22

Example: silicon (Used in computer chips) 3. Metalloids (7): located on the border of the dark zig-zag line. the dividing line between metals and nonmetals. Properties of Metalliods Behave as nonmetals, both chemically and physically. But their electrical conductivity resemble metals. semiconductors Example: silicon (Used in computer chips) 23

Noble Gases Group 18 or 8A VERY unreactive, monatomic gases Don’t form compounds!!! (Inert gases) Used in lighted “neon” signs and balloons. 24