Matter and Change Chemistry Chapter 1

Chemistry- What is it? Definition: study of composition, structure, and properties of matter and the changes it undergoes.

Main Branches of: 1. Organic chemistry- study of carbon-containing compounds. 2. Inorganic chemistry- study of compounds not containing carbon 3. Physical chemistry- study of properties, changes, and relationship between matter and energy. 4. Analytical chemistry- identification and composition of materials. 5. Biochemistry- study of chemistry in living things 6. Theoretical chemistry- uses math and computers to design and predict new compounds. -

Chemical- a substance which has definite composition. Research: Basic- done to increase knowledge. Applied- done to solve a specific problem. Development of Technology- the results of either basic or applied research can lead to the development of new products that can benefit man. However, they can come a long time after discovery.

Matter and its Properties Mass - amount of matter. Matter- has mass, takes up space. Building blocks of matter: Atom- smallest unit of an element with its properties. Element- pure substance, one kind of atom. Compound- substance with atoms of two or more elements chemically bonded.

Extensive property- depends upon the amount of matter volume mass amount of energy in the substance

Intensive property- does not depend on the amount of matter. melting point boiling point Density Color temperature

Changes in Matter Physical Change- a change in a substance that does not involve a change in its identity. Chemical Change- a change in which the substance is converted into two or more substances

Here are some physical and chemical change examples – (3:44)

Melting- change of solid to liquid Freezing- change of liquid to solid Change in State- Melting- change of solid to liquid Freezing- change of liquid to solid vaporization- change of liquid to gas condensation- change of gas to liquid Sublimation- change of solid to gas Examples of Sublimation: Dry ice (solid CO2) Snow and ice can sublime (clothes freeze dry) Naphthalene – moth ball ingredient

Three states of matter: Solid- definite volume and shape Liquid- definite volume, shape of container Gas- no definite volume or shape Plasma- made up of charged particles.

Physical Property- a characteristic that can be observed without changing the identity of the substance. (color, smell, freezing point, boiling point, viscosity, density, and magnetism) Chemical Property- describes a substances ability to transform into different substances. ( PH, reactivity with water, heat of combustion)

In a chemical reaction, the reactants undergo a chemical change to form the products. Energy changes also occur during the reaction. Exothermic- energy is given off during the reaction Endothermic- energy is absorbed during the reaction.

Evidence of a chemical reaction: Heat and/or light given off/temperature change Production of a gas. Formation of a precipitate A substance disappears A color change occurs A new odor is produced

What type of change would the burning of a candle be, physical or chemical?

Classification of matter: Mixtures- a combination of two or more different kinds of matter, each retaining its own characteristics. They can usually be separated by a physical process. Homogeneous- uniform composition(the same proportions of components throughout). Ex. Salt water, koolaid (yum!) Heterogeneous- not uniform throughout Ex. Sand and water, granite, blood

Pure substances- fixed composition and homogeneous Every sample has same characteristics Every sample has exactly same composition Two kinds of pure substances: Elements or compounds Separated only by chemical process. Most chemicals are considered to be pure even though most have some impurities in them.

The Elements The periodic table is an arrangement of the elements 1. The vertical columns are called GROUPS or FAMILIES. 2. The horizontal rows are called PERIODS.

Types of elements: Metals- a good conductor of heat and electricity. ductile- can be drawn into a wire malleable- can be hammered or rolled into thin sheets. tensile strength- resist breaking when pulled. most have a shiny appearance (LUSTER). EX. Copper, Iron, Aluminum, Sodium

Chemical Properties of Metals (5:53)

Nonmetals- poor conductor of heat and electricity tend to be brittle (easily broken) EX. Oxygen, Bromine, Sulfur Phosphorous – One of 5 solid non- metals. Red Phosphorous and White Phosphorous Too reactive to exist in pure form in nature. Show Phosphorous – Periodic videos.com

Metalloids-has characteristics of both metals and non-metals. solids at room temperature. less malleable than metals but less brittle than nonmetals. Many are used as semiconductors in common electronic devices(computers, calculators) There are six metalloids: Boron, Silicon, Germanium, Arsenic, Antimony, and Tellurium.

Now let’s look at non-metals and metalloids for 3 minutes!

Noble Gases- low reactivity rarely form compounds. a. EX. Helium, Argon

Symbols based on older names: Some of the symbols on the periodic table do not match the name of the element. That's because the symbol is taken from the older name of the element. See the chart on page 20. (Table 1-2) A Swedish chemist by the name of Berzelius introduced the first letter symbols for the elements.

Quiz on elements 31-60 is coming very soon!! Let’s make some flash cards!!! YAY!!!