Chemistry Unit 2: Matter

STUDY

LABS

matter

anything that has mass and volume (occupies a space)

1) includes pure substances and mixtures

atoms

the particles that make up all matter

4 Types of Matter

1) solid

2) liquid

3) gas

4) plasma

plasma

extremely hot gas

1) ex: stars

chemical properties

a substance’s ability to react or change into a new type of matter

1) ex: flammability, oxidization, reactivity

physical properties

characteristics of a substance that can be observed without a chemical reaction taking place

1) ex: texture, color, mass, odor, melting points, boiling points

pure substances

matter that consists of one type of atom or one type of molecule

1) have fixed compositions/ratios

1) includes compounds and elements

element

a substance composed of only one type of atom

1) = a pure substance

2) ex: Au

compound

a substance made of atoms of two or more chemically bonded elements in the same proportion

1) are separated chemically

2) ex: water (two H’s for every O)

mixtures

combinations of 2 or more substances

1) have variable compositions/ratios

2) includes homogenous and heterogenous mixtures

homogenous mixtures

mixtures with uniform compositions (evenly distributed)

1) also called solutions

2) are separated physically

3) ex: salt water (H₂O + Na), brass (Cu + Zn), air (N + O + others)

heterogenous mixtures

mixtures with non-uniform compositions

1) contain clearly-divided/distinct regions

2) are separated physically

3) ex: cereal, pizza, water + sand

chemical reaction

is just a chemical separation

chemical separation techniques

1) electrolysis

2) precipitation

electrolysis

chemical separation through electrical energy

physical separation techniques (10)

1) sifting

2) magnetic separation

3) filtration

4) decantation

5) evaporation

6) centrifuge

7) melting point

8) distillation

9) chromatography

10) crystallization

evaporation

liquid →

1) gas separates liquids from solids

centrifuge

= shaking a tube

1) separates objects by density

distillation

liquid → gas, then back to liquid

1) separates a liquid from another while conserving the liquid

chromatography

separating complex mixtures into their individual parts

energy

the ability to make a change

1) makes objects move and stop

2) two types = kinetic and potential energy

kinetic energy

the anergy of matter in motion

kinetic energy

energy of matter in motion

1) includes heat, mechanical, light, and electrical energy

potential energy

stored energy

1) includes chemical and nuclear energy

nuclear energy

the potential energy stored in a cell’s nucleus

First Law of Thermodynamics

energy cannot be created or destroyed

units for measuring temperature

1) Celsius (scientific standard)

2) Fahrenheit

3) Kelvins

Celsius

= standard measurement for temperature

1) 0-100 basic scale (0 = freezing point of water; 100 = boiling point)

2) coldest possible point = -275 degrees

Celsius to Fahrenheit conversion formula

T_F = (1.8F/C x T_C) + 32

1) look at slope lab for explanation

Fahrenheit to Celsius conversion formula

T_C = (T_F - 32)/1.8

Kelvins explained

because the lowest possible # on the Celsius scale is -275, Kelvins take that and start there

1) -275K = 0C

2) 1K = 1C

Celsius to Kelvin conversion formula

T_k = T_C + 273

solids

have a definite shape and volume

liquids

have a definite volume but do not have a definite shape

gas

has a definite shape but not a definite volume