1- states of matter

• solid- fixed shape and volume, particles touching, not moving

• liquid- fixed volume, unfixed shape, particles touching and moving a little

• gas- no fixed volume or shape, particles far apart and moving a lot

• plasma- no fixed volume or shape, particles far apart and moving a lot

1- properties of and changes in matter

• physical property

• anything you can see without changing the substance

• ex. transparency, boiling point, density, elasticity, malleability, brittleness, melting point

• chemical property

  • you can only see by changing the substance

  • ex. flammability, ability to rust, reactivity with vinegar

• physical change

  • when the identity of the substance doesn’t change (reversible)

  • ex. shattering, melting, separating (sand from gravel), dissolving, mixing, evaporating

• chemical change

  • when the identity of the substance changes (irreversible), during a chemical reaction

  • ex. rusting, bleaching, cooking, burning, exploding

• extensive property

  • depends on how much matter there is

  • ex. mass, weight, volume

• intensive property

  • doesn’t matter how much matter there is

  • ex. color, combustibility, density, melting point, malleability

chemical reaction

• 5 signs:

  • formation of a gas

  • color change/ emission of light

  • odor change

  • temp change

  • formation of a precipitate

• parts of a reaction

  • reactant, yield arrow, product. the compound on top of the yield arrow is the catalyst- it speeds up the reaction time.

Law of conservation of mass: in a closed system, mass cannot be created or destroyed

1- elements, compounds, and mixtures

Matter is classified into Pure Substances and Mixtures.

• Pure Substance- only one type of molecule, ex. water. can be elements or compounds.

  • element- an atom with specific characteristics, ex. hydrogen, iron, copper

    • can be metals or nonmetals, can’t be broken down further

  • compound- a molecule made of different atoms, ex. H2O, Na2

    • can be broken down into molecules using chemical charges

    • can be molecular, ionic, or intermetallic compounds

• ! ! pure substances can’t be broken down by physical means like distillation, filtration, chromatography, or evaporation ! !

• Mixture- combo of 2 substances, not chemically bonded. can be solutions or heterogeneous mixtures. Can be separated through physical changes.

  • solution (aka homogenous)- a group of molecules that are evenly distributed, ex. gasoline, air, and soda

• heterogeneous mixture- a solution that is unevenly distributed, ex. cereal/ milk, raisin bread

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2- precision and accuracy

• precision- the extent to which a series of measurements of the same quantity made in the same way agree with each other, not necessarily accurate.

• accuracy- the extent to which a measurement approaches the true value of a quantity

to find percent error: [(experimental - accepted) / accepted] * 100

🔎 look at page #9 in binder

2- significant figures

any digit in a measurement that is known with certainty, plus one final digit that’s slightly estimated

• rule 1- all nonzero digits are significant, ex. 254 has 3 sigfigs

• rule 2- zeros in between nonzeros are significant, ex. 2001 has 4 sigfigs

• rule 3- trailing zeros are only significant with a decimal after, ex. 2000.0 has 3 sigfigs

• rule 4- zeros in front of a nonzero don’t count, regardless of decimal, ex. 00.0004 has 1 sigfig

rules of rounding

• round up if trailing # is above 5………….. so 4566.89 rounded to 4 sigfigs is 4567

• leave it alone if trailing # is below 5…… so 4564.45 rounded to 4 sigfigs is 4564

for math operations (x / + -)

• always round according to the # with the least amount of decimal places (least accurate)

(10.3) x (0.01345) = 0.138535 → 0.139

🔎 **look at binder page #6,7,8,10 for more examples

2- scientific notation

• used when numbers are super big or super small, like atoms or planets

• numbers are written as a product (multiply) of 2 numbers, a **coefficient

** and 10 raised to a power.4500 →**4.5

** x 10³, coefficient is4.5coefficient must be from 1 - 9.**can’t be 10!!***if the # is greater than 10, exponent is positive and is = to the amount of spaces the decimal is moved left to write the # in scientific notation4.500 → 4.5 x 10³⤴⤴⤴ (move 3 times right, so power of 3)if the # is less than 10, the exponent wll be negative and is = to the amount of spaces the decimal is moved right.00012 → 1.2 x 10⁻⁴12 → 1.2 x 10¹.000,0007 → 7 x 10⁻⁷490 → 4.9 x 10²1000 →1 x 10³.987 → 9.87 x 10-¹1000 000 → 1 x 10⁶0.0375 → 3.75 x 10⁻²0.01 → 1 x 10⁻²596 → 5.96 x 10².001257 → 1.26 x 10⁻³0.000595 → 5.95 x 10⁻⁴2- density

mass**:

• ** theamount of matter an object contains. Doesn’t change unless you add/remove matterfind with a balance, use grams

volume**:

• ** theamount of space an object occupiesfind with liquid or a ruler, use mL for liquids or cm³ for solids or L for gases

density**:

** thecompactness of the molecules or particles of a substancemore compact molecules = greater densitythe relationship between an object’s mass and volume==mass== **/ volume = density

• • **remember:mL - volumeg - mass

g/mL org/cm³ org/L- density🔎 look at page # 17, 18, 19~~~~3- history of the atom

** discovered neutrons, current model used today🔎 look at page # 293- atomic structure

atom

• the smallest particle of an element that still has the chemical properties of the element

nucleus

• very small thing in the center of the atom

• made of at least one proton (p+) and usually at least 1 neutron (n*)

• surrounding the nucleus is a cloud of electrons (e-)

protons, neutrons, and electrons are called **Subatomic Particles

**protons (p+)

• located in nucleus, positive charge, big and heavy

neutrons (n)*

• located in nucleus, no charge, big and heavy

electrons (e-)

• outside the nucleus, negative charge, tiny and light

3- isotopes and ions

isotopes

• 2 atoms with different # of neutrons

• protons never changes

• neutrons can change

• have the same atomic #, different mass #s

ions

• an atom with a charge, # of electrons change

• if atom loses electrons, atom is + and (vice versa)

• protons, neutrons, atomic # and atomic mass stay the same

hyphen notation

• (element name) dash (mass number)

• ex. uranium-235

isotope notation (nuclear symbol)

• top - mass #……….. bottom - atomic #

• ex. U²³⁵₉₂ (pretend like that’s lined up)

nuclide- general term for a specific isotope of an element (probably don’t need to know this)

3- atomic #, atomic mass, mass number

**atomic #

** = protonsin a neutral atom, protons = electrons**mass #

** = protons + neutrons**atomic mass

** = the decimal in the element box**neutrons

** = mass # - atomic #electron configuration

periodic table

metals, nonmetals, and metalloids

periodic trends

valence electrons

cations and anions

nomenclature (ionic and molecular compounds; acids)

1. **states of matter

2. ****properties of and changes in matter

3. ****elements, compounds, and mixtures

8. precision and accuracysignificant figuresscientific notationdensityhistory of the atom

9. ****atomic structure

13. isotopes and ionsatomic #, atomic mass, mass numberelectron configurationperiodic table

14. ****metals, nonmetals, and metalloids

15. ****periodic trends