Chapter 1 Matter & Change

Transcription

1 Chapter 1 Matter & Change

2 Chemistry is the study of the composition, structure and properties of matter, the processes that matter undergoes, and the energy changes that accompany these processes.

3 There are six main branches of chemistry. There is overlap between these branches.

4 The study of most carbon containing compounds Propane, ethanol, alcohols, fuels, etc

5 The study of compounds not containing carbon. Many of these have organic fragments bonded to metals (organometallics). Acids, bases, minerals

6 The study of the properties and changes of matter and their relation to energy Will a compound explode or melt? Will something stretch or break?

7 The identification of the components and composition of materials Does this sample of blood contain lead or a certain drug?

8 The study of substances and processes occurring in living things Respiration, digestion, amino acids, molecular genetics all require biochemistry

9 The use of mathematics and computers to understand the principles behind observed chemical behavior and to design and predict the properties of new compounds

10 A chemical is any substance that has a definite composition or is used or produced in a chemical process.

11 Basic Research: research carried out to increase knowledge. Applied Research: research carried out to solve practical problems. Technological Development: uses existing knowledge to make life easier or more convenient.

12 Matter

13 Matter is anything that has mass and takes up space.

14 Mass is the amount of matter that an object contains.

15 Mass is the amount of matter Weight is the force of gravity on an object

16 An atom is the smallest unit of an element that maintains the chemical identity of that element. The building blocks of matter are atoms and molecules.

17 An element is a pure substance that cannot be broken down into simpler, stable substances and is made of one type of atom. The simplest form of matter that can exist under normal conditions.

18 A substance that can be broken down into simple stable substances. Each compound is made from atoms of two or more elements chemically bonded. A molecule is the smallest unit of an element or compound that retains the properties of that element or compound

19 There are two types of properties: Extensive properties depend on the amount of matter that is present. Ex: volume, mass, amount of energy Intensive properties do not depend on the amount of matter present. Ex: density, melting point, boiling point

20 A quality or condition of a substance that can be observed or measured without changing the substance s composition.

21 Melting point Boiling point Density Color Solubility Odor Hardness

22 Matter that is uniform and has a definite composition is called a substance Pure substances = one type of matter

23 A quality or condition of a substance that can be observed or measured without changing the substance s composition.

24 Melting point Boiling point Density Color Solubility Odor Hardness

25 Solid Liquid Gas Plasma

26 Has a definite shape Has a definite volume Does not take the shape of its container.

27 State that has a definite volume but an indefinite shape Form of matter that flows Takes the shape of its container Most are incompressible Do expand when they are heated

28 ostate that has neither definite shape nor volume oexpand to fill and take the shape and volume of its container oare compressible

29 oa high-temperature state of matter in which atoms lose most of their electrons oplasma is found in fluorescent bulbs

30 A physical change is one that alters a given material WITHOUT changing its composition, such as: Cutting Grinding Bending Melting/freezing (change of state)

31 The ability of a substance to undergo a changes that transform it into different substances Chemical properties are only observed when there is a chemical change

32 Energy change (+ or -) Color change Odor change Solid formed Liquid formed Gas formed

33 A change in which one or more substances are converted into different substances is called a chemical change or a chemical reaction.

34 The substances that react in a chemical change are called the reactants. The substances that are formed in the chemical reaction are called the products.

35 Two sides to a chemical reaction The reactants, or the starting substances The products, substances that are formed

36 The law of conservation of energy: states that in any physical change or chemical reaction, mass is neither created nor destroyed, it is conserved The mass of the reactants equals the mass of the products

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38 Are the following pure substances? Lemonade Ice Table salt

39 A mixture is a physical blend of two or more kinds of matter, each of which retains its own identity and properties.

40 There are two kinds of mixtures: Heterogeneous: not uniform in composition Homogeneous: completely uniform in composition. Solution is the special name given to homogeneous mixtures.

41 A pure substance is homogeneous. Pure substances differ from mixtures in the following ways: 1. Every sample of a pure substance has exactly the same properties. 2. Every sample of a pure substance has exactly the same composition.

42 Introduction to the Periodic Table

43 Each square on the Periodic Table represents an element. The square gives the element symbol, atomic number and atomic mass.

44 The vertical columns of the periodic table are called groups. The elements in a group have similar chemical properties.

45 The horizontal rows of elements in the periodic table are called periods. The two sets of elements placed below the table are called the lanthanide and actinide series.

46 Metal: an element that is a good conductor of heat and electricity Nonmetal: an element that is a poor conductor of heat and electricity Metalloid: an element that has properties of both metals and nonmetals

47 Elements in Group 18 of the periodic table. These elements are generally unreactive.