The Chemistry Guide

The Chemistry Guide​

Welcome to the wonderful world of chemistry, which is dreaded worldwide by almost all students. I'm going to give the basics on chemistry such as the reference tables and how to use them and then go into some deeper subjects, mainly Nuclear Energy and Oxidation and Reduction, some of the more difficult to grasp topics.

The Reference Tables:

The Periodic Table- Here you can find the following of each element: atomic mass, letter symbol, electron configuration and oxidation states. I'm going to break down one element, which is Ti (Titanium).



- In the upper left hand corner is where the atomic mass (47.88) is located. The atomic mass is the sum of the number of protons and neutrons found in the nucleus of an atom. Usually when calculating and using atomic masses you would round the number to the nearest whole number.
- Below that is the bolded number which represents the atomic number (22). This is the number of protons found in the nucleus of an atom.
- Just below the atomic number is the electron configuration (2-8-10-2), which basically means the arrangement of electrons in an atom.
- The upper right hand corner could consist of one or more numbers, in this case it is three. These three numbers are called oxidation states or numbers(+2, +3, +4). This represents the amount of oxidation which occurs in an atom, which will be gone into more deeply later.
- The letter symbol is the bolded letter located in the middle of the image (Ti), which would have some type of meaning for the symbol.
The following images are all examples of elements: these are just a few I pulled out.



You may notice the words 'period' and 'group' on your periodic tables. Here are what each stands for:
Period- is a horizontal section across the periodic table. For example K, Ca, and Sc are all in the same period. These range from 1-7.
Group- is a vertical section of the periodic table. For example Mg, Ca, and Sr are all in the same group. These range from 1-18.

Group 1 contains the Alkali Metals.
Group 2 consists of the Alkali Earth Metals.
Groups 3-12 are known as the Transition Metals.
Along the lower half of the bold line from lines 13-16 are the Other Metals.
Along the upper half of the bold line 13-17 are known as the Halogens.
Group 18 elements are known as the Noble Gases.
The separated elements at the bottom are known as the Rare Earth Metals.
H (Hydrogen) is know as a non-metal which is separated from the rest of the elements.

Table S- Properties of Selected Elements
Here you will find the following: atomic number, symbol, name, ionization energy, electro-negativity, melting point, boiling point and atomic radius.
I will choose one separate element and break that down, each follows accordingly. For example I will use Ag (Silver).

- The first sections is atomic number which has already been described above (47).
- Symbol is the chemical symbol which has been also described above (Ag).
- Next is the name which actually is behind the chemical symbol (Silver).
- After that comes Ionization energy which is the energy necessary to remove an electron from the neutral atom (731 kj/mol).
- Electro-negativity is the ability of an atom to attract electrons (1.9).
- Melting Point is the temperature at which a substance begins to transform to a liquid. The temperature is in Kelvin which can be converted from Celsius by adding 273 to whatever the Celsius temperature is and that will get you the temperature in Kelvin (1235 K).
- Boiling Point is the temperature at which a substance begins to boil, this is also listed in Kelvin (2485 K).
- The density is also listed for each element (g/cm^3)
- Atomic Radius is generally the size of the atom to it's furthest points (144 pm)

Nuclear Energy:
Nuclear Structure-


A. The image above represents a proton (positively charged). The 1 in the upper right hand corner represents mass (in this case 1) and the 1 in the lower left hand corner represents charge (in this case +1). It can also be represented with a P in place of the H.


B. The image above represents a neutron (no, or neutral, charge). The numbers in the lower and upper left hand corners have the same meaning as the Proton above.
C. Mass Defect- the mass of a nucleus is slightly less than the sum of it's protons and neutrons.
The greater the mass defect, the more stable the neutrons are. Stability of the nucleus depends on the ratio of protons to neutrons. P:N.

This is very basic chemistry and I can go much deeper into any topic. If you have any questions or want me to take notes for you on a specific topic just post. I pretty much can complete any topic accurately. Remember this is an incomplete guide and I can add anything anyone requests.

 

Can you explain how I change the empirical formula of a substance to molecular formula?

Example:

a) Calculate the empirical formula of a compound with the percentage composition 40% Calcium : 12% Carbon : 48% Oxygen.

I got: CaCO3

b) Using the empirical formula calculated and the molar mass given, determine the molecular formula for the compound.

Molar mass = 100 g mol^-1

Failed a test because of this, still have no clue...

 

When you are given the percent composition, you can find the empirical formula by following these steps:
- Assume you have 100g of a substance. This way, your percentages will be the number of grams. Example: 40% of a compound is carbon. 40% of 100 g is 40 grams.
- Change grams to moles. Since empirical formulas are mole comparisons, we need to put our numbers in moles first.
- Compare the number of moles of each to the smallest number of moles by dividing by the smallest number.
- Round your ratio to the nearest whole number. For example, 1.99987 can be rounded to 2, but 1.3333 cannot be rounded to 1.

 

Yea. I understand that. I now need to know how to convert the empirical formula to the molecular formula.

Example:

Determine the molecular formula for a substance with the empirical formula CaCO3 and a molar mass of 100 g mol^-1

 

Molar mass / Molar mass of empirical formula

 

Molar Mass of the CaCO3 or whatever, divided by the molar mass of the simplest form of the CaCO3, I believe.

 

Rofl... Seriously, I'm a prat. I've failed an exam over this and I was nine tenths the way there.

Thanks guys.

 

No problem, hope that answered your question.

 

Chemistry is too broad, you should have focused on The Periodic Table and the elements.

Well done, though.

 

I did focus on the periodic table and the elements...
The reference tables are the same thing as the periodic table, which is contained inside.

 

Can you tell me how to syntesis metildeoxymethamphetamine ?

 

Anarchist's cookbook ftw


nice guide, i love chemistry!

 

I don't know much about the substance but I know it's actually called "methyldioxymethamphetamine" and I know it only has single bonds.

 

LOL Just found book wrote by Uncle fester ! He's not only from adams family but he wrote 2 books about cooking amphetamines !

I'm not from USa so we we call it metildioximetaamfetaminas , i sometimes make mistakes :'(

 

I'm going to bookmark this and check on it fro time to time. I might need it for my chemistry class.
Keep updating plox!

 

nice guide put in alot of effort

 

Thanks for this loolz.

 

Unintentional pun? You can't break down elements! lawlaw

 

No offense but science doesn't interest me, Nice guide anyways.

 

rofl nice i dont do chemisrty lol.