Warm-Up (9/26)(1.) List and describe in detail the 5 components

that make up a good science lab report.(2.) Write the following in scientific notation:

a.) 0.00076 gb.) 345,900,000 Lc.) 82.1 m

(3.) Convert the following measurements:a.) 23 m cmb.) 9.48 mL dLc.) 7.6 Mg pg

Answers to Warm-Up (9/26)

(1.) Introduction, Materials, Procedures, Data Table, Conclusion(2.) a.) 7.6 x 10-4 g

b.) 3.459 x 108 Lc.) 8.21 x 101 m

(3.) a.) 2.3 x 103 cmb.) 9.48 x 10-2dLc.) 7.6 x 1018 pg

Chapter 2Matter and Change

Ms. WangLawndale High School

Describing Matter Properties used to describe matter

can be classified as extensive or intensive

Extensive and IntensiveExtensive – depends on the amount of matter in a sample (mass or volume)

Intensive – depends on the type of matter in a sample (hardness/softness)

Identifying Substances

Physical Property – a quality or condition of a substance that can be observed or measured without changing the substance’s composition

Look at the 3 objects I have on the front demo table…Every sample of a given substance has identical intensive properties because every sample has the same composition.

States of Matter

Solid – form of matter that has a definite shape and volume

States of Matter Liquid –

form of matter that has an indefinite shape, flow, yet has a fixed volume

States of Matter

Gas – form of matter that takes both the shape and volume of its container

Mixtures(Observe the oil and vinegar)

A physical blend of two or more components

Types of Mixtures(1.) Homogeneous – a mixture in which the composition IS uniform throughout (oil, vinegar)

(2.) Heterogeneous – a mixture in which the composition IS NOT uniform throughout (chicken soup, salad, oil & vinegar)

Separating Mixtures(Observe the heterogeneous mixture of Styrofoam, pennies, and water)

You can use a variety of methods to separate mixtures depending on the substances and their physical properties.

• Filtration – process that separates a solid from a liquid in a heterogeneous mixture (cooked pasta in a colander, coffee)

• Distillation – a process involving liquid being boiled to produce a vapor, which is then condensed back to a liquid

Substances vs. Mixtures

Substance – composition of a material is fixed (Elements and Compounds)

Mixture – composition of a material varies (Homogeneous and Heterogeneous Mixtures)

Elements and Compounds Element –

simplest form of matter that has a unique set of properties

Compound – substance that contains two or more elements chemically combined in a fixed proportion

Symbols and Formulas Chemists use chemical symbols to

represent elements, and chemical formulas to represent compounds

Each element is represented by a 1- or 2-letter chemical symbol

The 1st letter is always CAPITALIZED, while the 2nd letter (if used) is lowercase.

(Example: H, O, C, Cl, He, Na)

Physical Changes During a physical change, properties of

a material change, but the composition of the material does not.

Physical Changes include…

BOILING

MELTING

FREEZING

CONDENSING

BREAKING

CUTTING

CRUSHING

Chemical Change A change that produces matter with a

different composition than the original matter

Reactant versus Product

Reactants - Substance present at the beginning of the reaction (left side)

Products - Substance present at the end of the reaction (right side)

Reactant Product

(1.) Transfer of energy (heat)

(2.) Change in color

(3.) Produces a gas (bubbles)

(4.) Forms a precipitate (solid that forms and settles out of a liquid mixture)

Recognizing Chemical Changes…

Conservation of Mass During any chemical reaction, the

mass of the products is always equal to the mass of the reactants

Example: 10 grams of ice melts into 10 grams of water

Law of Conservation of Mass – mass is conserved in any physical change or chemical reaction (mass is neither created nor destroyed)

Classwork

Sec 2-1 #’s 5, 8 Sec 2-2 #’s 11, 14, 16, 17 Sec 2-3 #’s 20, 21, 24, 25, 26, 27 Sec 2-4 #”s 29, 30, 31, 32, 33, 34