Chemistry Chapter 1.1. Matter and Change

Transcription

1 Chemistry Chapter 1.1 Matter and Change

2 1.1 Chemistry is a Physical Science Objectives 1. Define chemistry. 2. List examples of the branches of chemistry. 3. Compare and contrast basic research, applied research, and technological development

3 1.1 What is Chemistry? The study of: Composition what something is made of Structure what is its shape Properties of matter The processes that matter undergoes The energy changes that accompany these processes Molar mass Appearance Odor Density g/mol Colorless gas Odorless Melting point 56.6 C 1.98 kg/m 3 (gas at 1 atm and 0 C) Solubility in water 1.45 g/l at 25 C, 100 kpa

4 1.1 What is Chemistry? Chemical Any substance that has a definite composition

5 1.1 What is Chemistry? Is chemistry a physical or biological science? Physical sciences non living things Biological sciences living things Chemistry is the CENTRAL science

6 1.1 Branches of Chemistry Organic Study of most carbon containing compounds Inorganic Study of nonorganic substances Physical Study of the properties and changes of matter and their relation to energy

7 1.1 Branches of Chemistry Analytical The identification of the components and composition of materials Biochemistry The study of substances and processes occurring in living things Theoretical Use of math and computers to understand the principles behind observed chemical behavior and to design and predict the properties of new compounds

8 1.1 Chemical Research Basic Research Driven purely by curiosity and a desire to know more Example: studies of the properties of elements Applied Research Driven by a desire to solve a problem or answer a specific question Example: development of new refrigerants to reduce damage to the ozone layer Technological Development The production and use of products that improve our quality of life. Example: 3D printers

9 Chemistry Chapter 1.2 Matter and Change

10 1.2 Matter and Its Properties Objectives 1. Distinguish between the physical properties and chemical properties of matter. 2. Classify changes of matter as physical or chemical. 3. Explain the gas, liquid and solid states in terms of particles. 4. Explain how the law of conservation of energy applies to changes of matter. 5. Distinguish between a mixture and a pure substance.

11 1.2 Matter Anything that has mass and takes up space Mass Measure of the amount of matter Volume Amount of 3D space an object occupies

12 1.2 Building Blocks of Matter Atom Smallest unit of an element that maintains the chemical identity of that element Element Pure substance that cannot be separated or broken down into simpler substances by chemical means; all atoms of an element are (mostly) the same

13 1.2 Building Blocks of Matter Compound A substance that can be broken down into simple stable substances; made from the atoms of two or more DIFFERENT elements that are chemically bonded Molecule Smallest unit of an element or compound that retains all of the properties of that substance

14 1.2 Properties & Changes in Matter Every element and compound have characteristic properties Scientists use these properties to distinguish between substances and to separate them Changes in matter always involved changes in energy Law of Conservation of Energy energy cannot be created or destroyed, just transformed from one form to another

15 1.2 Physical Properties Characteristic that can be observed or measured without changing the identity of the substances E.g. melting point, boiling point Physical change Change that doesn t involve a change in the identity of the substance Cutting, grinding, sanding, melting, boiling

16 1.2 Properties of Matter Physical properties are either intensive or extensive Intensive properties Do NOT depend on the amount of matter Extensive properties Depend on the amount of matter

17 1.2 Change of State An important class of physical changes A physical change of a substances from one state to another COMMON states of matter Solid Liquid Gas Plasma

18 1.2 States of Matter Solid Definite volume and shape Particles vibrate Compact with strong attractive forces Liquid Definite volume but indefinite shape Particles close but are free to move past each other Move more rapidly than solids

19 1.2 States of Matter Gas No definite volume or shape Very little to no attractive forces Want to spread out as much as possible Plasma High temperature physical state of matter in which atoms lose most of their e - Found in fluorescent bulbs

20 1.2 Chemical Change Chemical reaction 1 or more substances are converted into different substances reactants products Pb(NO 3 ) 2 + 2KI PbI 2 + 2KNO 3

21 1.2 Chemical Properties Relates to substance s ability to undergo change that transforms it into a different substance What will that molecule react with? Examples: rust 4 Fe + 3O 2 2Fe 2 O 3 Combustion

22 1.2 Matter Classification Pure substance Has a fixed composition and differs from a mixture because EVERY sample has the same composition and properties Can be compounds or elements

23 1.2 Matter Classification Mixture A blend of two or more kinds of matter, each of which retain its own identity and properties Mixtures can be physically separated Homogeneous or heterogeneous

24 1.2 Mixtures Homogeneous Uniform composition throughout Solutions Heterogeneous Composition is NOT uniform throughout the mixture Colloids and suspensions

25 Chemistry Chapter 1.3 Matter and Change

26 1.3 Elements Objectives 1. Use a periodic table to name elements, given their symbols. 2. Use a periodic table to write the symbols of elements, given their names. 3. Describe the arrangement of the periodic table. 4. List the characteristics that distinguish metals, nonmetals and metalloids.

27 1.3 Periodic Table Systematic grouping of chemical elements Antoine Lavoisier first to systematically group 33 elements into gases, metals, nonmetals and earths in 1789 Dmitri Mendeleev credited with modern periodic table in 1869, revised to more modern form in 1871

28 1.3 Periodic Table Groups/families Vertical columns Similar chemical properties Periods Horizontal rows Properties change somewhat regularly across a period Increasing atomic number

29 1.3 Metals Solid at room temp (except Hg) Conduct heat and electricity Malleable Can hammer or roll into thin sheets and shape Ductile drawn into a wire High tensile strength resists breaking when pulled

30 1.3 Nonmetals Solid, liquid or gas at room temp Poor conductors of heat and electricity Solid nonmetals tend to be brittle Includes the noble gases Nonreactive elements Used in lighting (Ne, Ar, Kr, Xe)

31 1.3 Metalloids Have properties between metals and nonmetals Solid at room temp Tend to be semiconductors Used in solid state circuitry found in computers, digital watches, TV and radios Antimony Silicon Arsenic

32 Chemistry Chapter 1 Matter and Change