Comprehensive Chemistry Key Terms: Elements, Mixtures, Measurements, and Energy

element

thing like on the periodic table

pure substance

A sample of matter, either a single element or a single compound, that has definite chemical and physical properties

Compound

A substance made up of atoms of two or more different elements joined by chemical bonds (pure substance)

hetrogeneous mixture

a mixture in which pure substances are unevenly distributed throughout the mixture

homogenous mixture (solution)

a mixture in which the composition is uniform throughout

pysical change

a change of matter from one form to another without a change in chemical properties (still same compounds)

kilo

10^3

hecto

10^2

deka

10^1 (10)

deci

10^-1

centi

10^-2

mili

10^-3

mirco

10^-6

mega

10^6

giga

10^9

nano

10^-9

length

meter (m)

mass

kilogram (kg)

time

second

cal to joule

1 cal = 4.184 J

desnity

mass/volume

k

c+273.15

c

f-32/1.8

1 Cal

1000 cal

exo

release energy

endo

gain energy

specific heat form

q (heat)= mass x specific heat capacity x (final-initial temperature)

comp

q (heat)= mass x specific heat capacity x (final-initial temperature) formula

expand terms then move all of each to either side

intesive property

does not depend on the amount of matter present

(color, smell, boiling temp)

extensive property

a property that depends on the amount of matter in a sample

macroscopic

visible to the naked eye

scientific laws

verbal/mathematical statements-what happens every time

scientific therories

exclamations for why things happen- explain why it happens

Significant Figures rule

1. all non zero

2. interior

3. zeros after a number only with decimal

when adding sf WITHIN equation

write it out with the trick

When solving equations

keep the ratio they have asked for same order

Scientific Method Steps

Observations, Hypothesis, Experiment/Data Collection, Conclusion, If nessasary restart

Matter

Anything that has mass and takes up space

Atoms

smallest unit of matter

molecules

Groups of two or more atoms held together by chemical bonds

Forms of enegry