Chapter 1Matter and Change

1.1 - Chemistry is a Physical Science

• Chemistry – the study of the composition, structure, and properties of matter and the energy changes that accompany these changes

• branches of chemistry– organic– inorganic– physical(p-chem)– analytical– biochemistry– theoretical

• chemical – substance w/ definite composition• examples – H2O, C12H22O11, Au• everything other than NRG or a force

– chemical Rx(reaction) – a change in the composition of a substance• creates new substances with different properties• video

1.2 Matter and Its Properties–matter – takes up space, has mass• anything that possess inertia

–mass – measure of amount of matter• measure of inertia

• classification of matter–by phase• solid, liquid, gas, …

–by composition• compound, mixture, element,…

• states /phases of matter– solid – definite volume and definite shape• definite volume – small distance between particles

– packed tightly together

• definite shape – particles organized in a fixed position– pattern or organized crystal

– liquid – definite volume, no definite shape• definite volume – small distance between particles

– packed tightly together» distance is very similar between solid particles and liquid

particles – myth – particles of liquid move apart when a solid melts

• no definite shape – particles in no order or pattern– particles randomly arranged– no crystal stucture

– gas – no definite volume, no definite shape• no definite volume – particles large distance from one

another– distance between gas particles is ~ 1000 times further than

solids or liquids» what is in the space between gas particles???

• no definite shape – particles in no order or pattern– particles randomly arranged, no crystal stucture

– plasma – high NRG phase of matter • composed of positive and negative particles

– not attracted together

• composed of pieces of atoms• most abundant phase of matter in the universe

– Bose-Einstein condensate – phase of matter that occurs at temperatures near absolute zero(-273oC or -460oF)• colder than a solid• atoms all join together/condense to a single “super”

atom

Classification of Matter by composition

MATTERHomogeneous

-same thru-outHeterogeneous

-different thru-out

Mixture

-2 or more subst.

-easily separated thru physical means

-no formula

- retain same properties

-may consist of diff. phases

Pure substance

-one type of matter only

- oxygen, water

Solution

-one phase, 2 or more substances

-air, pop, stainless steel

Element

-simplest

-one type of atom

-lead, oxygen

Compound

-2 or more subst.

-chem Rx to separate

-specific formula

- different properties

-water, carbon dioxide, sulfuric acid

• physical property– properties that can be observed/measured

without changing the substance• density• luster/color• melting/boiling point

• chemical property– properties that describe how a substance reacts

with other substances in a chemical change• highly reactive• combines with oxygen• burns in air

• physical change – change in appearance or phase of matter– no change in composition– same substance, looks different

• dissolving sugar in water• melting ice

• chemical change – change in the identity or composition of the substance– chemical Rx needs to occur

• burning paper• baking soda and vinegar(volcano Rx)• reactant (s)– starting substance(s) = paper, baking soda,

vinegar• product(s)- substance(s) created = carbon dioxide, water

vapor

• evidence of a chemical Rx1. change in NRG(absorbed or released)• substance gets hotter or colder

2. evolution of a gas• bubbling• change in odor

3. formation of light• burning match• glow stick

4. formation of electricity• batteries/dry cells

5. formation of a precipitate• precipitate = insoluble solid that falls out of solution

– soap scum– hard water deposits/crust around faucet

6. color change• chemical indicators – litmus• not always reliable

Section 1.3 – Elements• intro to periodic table– vertical columns – groups/families• similar properties

– horizontal rows – period/series• properties change throughout the row

– bottom two rows• placed there to save space• fit in order on periodic table

• types of elements–metals• excellent conductor electricity• ductile• tenacious/high tensile strength•malleable• good conductor heat• shiny/luster•most solids/high melting and boiling

points

• nonmetals–nonconductor of electricity•worst conducting metal 100,000 better

than best conducting nonmetal–poor conductor of heat• low melting/boiling points

–brittle– dull appearance

• metalloids– properties of both metal and nonmetal• less malleable, not as brittle• semiconductors

– computer chips, LED lights

• noble gases– chemically inert– gases at room temp