This is my Chemistry Journal. I wrote all the things I have learned in Chemistry in this page. I hope you might learn something from this..

What is Chemistry?

Chemistry is the science of matter.  Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds.

Branches of Chemistry

1. Organic Chemistry- study of compounds of carbon.
2. Inorganic Chemistry- study of all elements and compounds other than organic compounds.
3. Physical Chemistry- study of theoretical aspects of the structure and changes of matter.
4. Analytical Chemistry- study of what is present (qualitative) and how much is present (quantitative) in a compound.
5. Biochemistry- chemistry of biologically important elements and compounds.

History of Chemistry

1. Pre-historic Man

-use of fire

-brick making

-metallurgy

-pottery

b) 400 B.C

- 4 element theory was proposed.

-Aristotle proposed that there were also 4 fundamental properties.

c)  First Century

- Art of Egyptians, philosophical speculations of the Greeks form the beginning of a body of chemical knowledge.

-1^st book in Chemistry was written in Egypt.

-Beginning of Alchemy in China.

d) 12^th Century

-Alchemy reached Europe (Alchemy is the tranation of one element to another).

e) 16^th-17^th Century

-Chemistry applied to medicine.

-Study of gases begun.

-First textbook in Chemistry was written in1597.

-Robert Boyle studied gases and criticized the basic ideas of Alchemy in his book “The Skeptical Chemist”.

f) 18^th Century

-The Phlogiston Theory was proposed by George Ernst Stahl based on earlier theories of Johann Becher.

- Carl Scheelem Joseph Priestly, Joseph Black and Henry Cavendish worked on gases.

g) 19^th-20^th Century

- John Dalton proposed the Atomic Theory.

-Dmitri Mendleer developed the periodic law and periodic table.

-Development of these theories.

Significant Figures

Rules to determine Significant figures

1. All nonzero digits are ALWAYS SIGNIFICANT.
2. Leading zeros are never significant.
3. Captive zeros are always significant.
4. Trailing zeros may or may not be significant. Trailing zeros are significant ONLY if the number has a decimal point.

Scientific Notation

is a way of writing numbers that are too large or too small to be conveniently written in standard decaimal notation.

Conversion in

Length:

1km=1000m

1m=100cm

1cm=10mm

1in=2.54cm

1ft=12in

1m=39.37in

1mile=1.6093km

Pressure:

1atm=14.7psi

1atm=76cm

1atm=760mmhg

1atm=760torr

1atm=101325Pa

1Pa=0.9869atm

Mole:

1 mole element=N atoms

1 mole compound= N molecules

1 mole m+nm= N formula units

1 mole element= atomic mass(grams)

Volume:

1 cubic centimeter = 1000 cubic millimeter

1 cubic decimeter = 1000 cubic centimetre

 1 cubic meter = 1000 cubic decimetre

 1 liter/ litre = .001 cubic meter

1 liter / litre = 10 deciliter

 1 deciliter = 10 centiliter

1 centiliter = 10 milliliter

1 cubic foot = 1728 cubic inches

1 cubic yard = 27 cubic feet

Temperature:

Commonly used scales are:

1. Fahrenheit- named after Gabriel Daniel Fahrenheit (a German Physicist).
2. Celsius-named after Anders Celsius (a Swedish astronomer).
3. Kelvin-named after William Thomson (a British physicist and mathematician).

Formula for:

Fahrenheit: °C  x  9/5 + 32 = °F

Celsius: (°F  -  32)  x  5/9 = °C

Kelvin: k=°C +273 or °C =k-273

Matter:

Heterogeneous Mixtures- mixtures not uniform in appearance.

Homogeneous Mixtures- mixtures that are same in appearance.

Mixture- a combination of 2 or more substances.

Intensive- independent of the amount.

Extensive- dependent on amount.

Table 3-6b Orbitals and Electron Capacity of the First Four Principle Energy Levels

Submitted by: Paulaine Cordon

SOF 3-Pearl