Chemistry Test 1

1033

F—>C

5/9(F-32)

C—>K

C+273.15

F—>K

5/9(F-32)+273.15

K—>F

9/5(K-273.15)+32

Scientific Notation, (±)

±Co , Convert to same ex

Scientific Notation, (Multi/Divi)

Multipy/Divide Co, ± ex

Significant Figures

Non-0’s, 0’s between sig figs, trailing 0’s

Non-Significant Figures

Leading 0’s

± Sig Fig’s

Fewest decimal places

(Multi/Divi) Sig Fig’s

Fewest sig fig’s

Mega

(M)6

Kilo

(K)3

Centi

(C)-2

Milli

(M)-3

Micro

(µ)-6

Nano

(n)-9

Pico

(p)-12

Physical Change

Changes in appearance, not composition

Chemical Change

Changes in composition

Pure Substance

Has a fixed composition

Element

Pure substance made of one type of atom.

Compound

Pure substance made of two or more types of atoms chemically bonded

Mixture

Physical combination of substances

Protons

Positive charge, located in the nucleus

Neutrons

No charge, located in the nucleus

Electrons

Negative charge, orbiting the nucleus

Definite Proportions

A compound always has the same elements in the same proportion by mass.

Multiple Proportions

When elements combine in more than one ratio to form different compounds, those ratios are small whole numbers

Neutral Atom

Number of protons = number of electrons

Ion

Number of electrons differs from protons

Neutrons

Mass number - atomic number

Atomic Number (Z)

Number of protons

Mass Number (A)

Number of protons + neutrons

Moles to Particles

Use Avogadro's number

Moles to Mass

Use molar mass