CHEMISTRY EXAM 1

HCl

HNO₃

HC₂H₃O₂/C₂H₃OOH

H₂SO₄

H₃PO₄

H₂CO₃

HClO₃

1+,2+

2+,3+

1+,2+

3+,5+

2+,3+

2+, 4+

The study of matter, its composition, and the changes it undergoes

• 1.Biochemistry- study of biological chemicals
• 2.Organic- carbon based compounds
• 3.Inorganic- all other elements
• 4.Physical- theory and concepts
• 5.analytical- methods of analysis
• 6.nuclear- radioactive materials

• 1.Apply logical, organized reason to any observation made
• 2.Form Hypothesis
• 3.Reject or confirm (trial&error) hypothesis through experiment

anything that has mass and takes up space

measure of the amount of matter that object contains

the effect of gravity on matter

can be seen without changing the composition of material

size doesn't matter

ex.color, ordor, density, melting point, boiling point, taste, feel, compressibility, magnetism, duetility, solubility, conductivity

size does matter

ex.mass, length, etc.

change in composition

composition isnt altered

• changes in state
• dissolving
• pulverizing

composition is altered

• rusting
• combustion
• fermentation

• 1.heat energy
• 2.light energy
• 3.electric energy
• 4.water
• 5.catalyst

energy is released (heat or light)

energy is absorbed (temp. drops)

smallest unit of an element that has all the properties of the element

smallest unit of a pure substance that has all the properties of that substance

may have one atom or more

molecule that contains two atoms

two or more atoms of one element

contains at least 2 atoms of two or more elements

a combination of two or more pure substances

uniform composition

non-uniform composition

cannot be converted to simplier form by a chemical reaction

ex.hydrogen, oxygen

two or more elements in a definite, reproducible way

ex.water

measurements and observations that you make

data obtained from experiments

defines the quantities being measured

must have units

10⁶

10³

10²

10¹

10^-1

1.057

2.2

1.094

2.54

how close to the true value

how close to each other

• leading zeros are not significant
• captive zeros are significant
• trailing zeros are significant

9/5C+32

5/9(F-32)

C+273.15

D=mass/volume

SG=density of substance/ density of reference

1.00g/cm³

1.29g/l

(theoretical-experimental)/theoretical

used to represent each element

used to represent compounds

consists of the symbol of the elements found on the compound

the protons and neutrons are tightly bound together to form the central portion of an atom

• located in the nucleus
• charge of 1+
• mass of 1u

• located in the nucleus
• no charge
• mass of 1u

• located outside the nucleus
• charge of 1-
• mass of 1/1836u

equal to the number of protons in the nucleus of the atom

represented by the symbol of Z

equal to the sum of the number of protons and neutrons in the nucleus of the atom

represented by the symbol A

atoms that contain the same number of protons but a different numbe of neutrons

• they have the same atomic # but different mass #
• same #of electrons outside that nucleus

extremely small size of atoms and molecules make it inconvenient to use their actual masses

comparisons of actual masses

the relative mass of an average atom of the element expressed in atomic mass unit

the number given at the bottom ofthe box containing the symbol of each element

relative mass of a molecule in the atomic mass unit

obtained by adding together the atomic weigth of all the atoms in the molecule

(isotope percentage)(isotope mass)/ 100

the number of atoms in one mole is equal to Avogardro's Number

6.022x10²³

• Know the formula
• 2.Know the formula weight
• 3.divide the number of atoms by the formula weight

• ex.H₃PO₄=98.00
• H=3.03/98.00=3.09%

GOOD JOB!!!