Chapter 1 Chemistry: What is Chemistry

1. Chapter 1Chemistry: What is Chemistry (A whole lot of fun!)

2. Objectives • Describe chemistry • Classify and describe the types of matter • Describe physical and chemical properties • Describe physical and chemical changes • Recognize clues a chemical change has occurred

3. What is Chemistry? • The study of the matter, its composition, properties, and the changes it undergoes. • Applied Chemistry is the using chemistry to attain certain goals, in fields like medicine, agriculture, and manufacturing • Pure chemistry gathers knowledge for knowledge sake

4. Types of Chemistry • Analytical Chemistry studies composition of substances. • Inorganic Chemistry substances without carbon • Organic Chemistry compounds containing carbon • Biochemistry- Chemistry of living things • Physical Chemistry studies behavior of substances

5. Chemistry is • A natural science with a language and its own vocabulary. • A way of thinking.

6. What is Matter? • Matter is anything that takes up space and has mass. • Mass is the amount of matter in an object. • Mass is resistance to change in motion along a smooth and level surface. • Volume – measure of 3D space

7. Types of Matter • Pure Substance- a particular kind of matter - pure • Mixture- more than one kind of matter

8. Substances • Elements- simplest kind of matter • Cannot be broken down • All one kind of atom. • Compounds are substances that can be broken down by chemical methods • When they are broken down, the pieces have completely different properties than the compound. • Made of molecules- two or more atoms

9. Atoms • The smallest unit of an element that maintains the properties of that element.

11. Elements • A pure substance made of only one kind of atom • Currently 118 elements • 90 natural 28 synthetic • Found on periodic table • Identified by 1,2, or 3 letter chemical symbol

12. Chemical symbols • There are 118 elements • First letter always capitalized second and third never • Don’t need to memorize • Some are from Latin or other languages H= Hydrogen Au= Gold Uub= Ununbibium

13. Elements cont. • Majority are metals (found on the left side of periodic table) • Nonmetals on the right of stair step line

14. Compounds • A substance that is made from the atoms of two or more elements that are chemically bonded • Chemical Formula – Indicates type and number atoms in a compound • Ex. H2O = 2 Hydrogen atoms and 1 Oxygen atom

15. Compounds cont. • Molecular Compounds made from nonmetallic atoms • Ionic Compounds contain ions • (usually a metal and nonmetal) Molecular or Ionic? C6H12O6 MgCl2 CO2 Ionic Molecular Molecular

16. Metals • Luster • Good conductor of heat and electricity • Malleability • Ductility • High tensile strength

17. Nonmetals • Many nonmetals are gases at room temperature • Solid nonmetals tend to be brittle • Poor conductors of heat and electricity

18. Mixtures • A blend of two or more kinds of matter, each of which retains its own identity and properties • The components of mixtures can usually be separated through physical means • filtration, distillation, chromatography

19. Filtration • Uses a filter to separate substances • Solid from a liquid

21. Distillation • Separates based on boiling points • liquids

23. Chromatography • Separates based on polarity • What?!?!?!?!?! • We’ll get to that later -Liquids or gases

24. Heterogeneous Mixtures • Called suspensions and colloids • Not uniform throughout • Ex. Chocolate chip cookie, gravel, soil

25. Homogeneous Mixture • Called solutions • Mixtures that are uniform throughout • Kool-aid, air, gold ring

26. Solutions • Like all mixtures, they keep the properties of the components. • Can be separated by physical means • Not easily separated- can be separated.

27. Solutions • Homogeneous mixture • Mixed molecule by molecule • Can occur between any state of matter. • Solid in liquid- Kool-aid • Liquid in liquid- antifreeze • Gas in gas- air • Solid in solid - brass • Liquid in gas- water vapor

28. Flowchart of Matter

29. Element Compound Mixture Which is it?

30. Physical Properties • A property that can be observed and measured without changing the substance. • Ex. melting point, boiling point, density, hardness, color, odor • Freezing Point vs. Melting Point?

31. States of matter • Solid- matter that can not flow and has definite volume. • Liquid- definite volume but takes the shape of its container (flows). • Gas- a substance without definite volume or shape and can flow.

32. Physical Change • A change that changes appearances, without changing the composition. • Freezing – liquid to solid • Melting – solid to liquid • Boiling – liquid to vapor • Condensation – vapor to liquid • Sublimation – solid to vapor • Deposition – vapor to solid

33. Chemical Properties • Relates to a substances ability to undergo changes that transform it into different substances • Ex. combust, oxidize, neutralize

34. Chemical Change • A change in which one or more substances are converted into different substances Ex. combustion, oxidation, neutralization

35. Chemical Reactions • Carbon + Oxygen  Carbon Dioxide • Read as “Carbon and (plus) oxygen yields carbon dioxide • Carbon and Oxygen are reactants • Carbon Dioxide is the product

36. Chemical Reactions • When one or more substances are changed into new substances. • Reactants- stuff you start with • Products- What you make • NEW PROPERTIES • Not easily reversed

37. Indications of a chemical reaction • Energy absorbed or released • Color change • Gas is released • Light given off • Precipitate- solid that separates from solution p.255 in text

38. Example

39. Homework • Page 21 #’s 25,31,34,53,54,56,68