Ethyne

Yellow ball=hydrogen atom

Black ball=carbon atom

Wood stick=polar covalent bond

Spring=covalent bond

Ethyne is shown above and Ethyne above has formula of HC2H. Ethyne molecule has a 180 degree bond angle where atoms that are alike to each are positioned as far apart as possible. Thus, it seems that ethyne has a linear structure since atoms are positioned in one line. Each hydrogen atoms are single bonded to carbon atom to follow duet rule while carbon atom are triple bonded to another its atom to satisfy its octet rule.

Ethene

Yellow ball=hydrogen atom
Black ball=carbon atom
Wood stick=polar covalent bond
Spring=covalent bond
The photograph shows ethene which has formula of C2H4. We think that two bent or V- shaped structures double bonding each other at carbon atom forms ethene. To be specific, the reason wht there is one bent structure is because there are still one lone pair that causes other two hydrogen atoms to form V-shape. It is also based on two hydrogen atoms attaching to one carbon atom. There is a single bond between hydrogen atom and carbon atom in order to follow duet rule for hydrogen atom. In other hand, there are two double bond between two bent shape structure at carbon atom in order to follow octet rule. Nevertheless, other researches have shown that ethene has form of alkenes.

Ethanol

Yellow ball=hydrogen atom
Red ball=oxygen atom
Black ball=carbon atom

What photograph shows is Ethanol molecule and its formula is CH3CH2OH or C2H6O as an empirical formula. In our opinion, there are three types of molecule structure that makes up ethanol and there are linear structure, bent or V-shaped structure, and one trigonal pyramid. While oxygen and hydrogen atoms are bonded together to form linear structure, 3 hydrogen atoms bonding with one carbon atom produced similar structure of trigonal pyramid. Lastly, bent or V-shaped structure is based on two hydrogen atoms bonding with one carbon atom. Therefore, we think that three structures single bonding each other forms ethanol molecule.

Methanol

Yellow ball=hydrogen atom
Black ball=carbon atom
Red ball=oxygen atom
Wood stick=polar covalent bond
The photograph above shows methanol molecule that has chemical formula CH3OH or CH4O. The structure of the methanol molecule is based on one trigonal pyramid structure for 3 hydrogen atoms in one carbon atom and one linear structure that bonded with oxygen and hydrogen atoms. Therefore, both trigonal pyramid and linear structure are single bonded each other to form methanol molecule. Another way of saying the methanol structure will be this: it is composed of 3 elements, carbon, oxygen, and hydrogen. One carbon atom with 3 hydrogen atoms is bonded to oxygen atom that is bonded with one hydrogen. All of the bonds in methanol molecule are single bonds.

Ethane

Black ball=carbon atom
Yellow ball=hydrogen atom
Wood stick=polar covalent bond
Ethane molecule is shown above and ethane is chemical compound with chemical formula C2H6. In our opinion, we think that the structure of the Ethane is based on two trigonal pyramid joining together since there is still single lone electron that pushes other three bonds of hydrogen that connects carbon atom. However, their actual structure is aliphatic hydrocarbon that contains two-carbon alkane. Bonds that connects either hydrogen atoms or carbon atoms satisfies duet or octet rule for ethane molecule. For example, carbon atom is sharing 4 pairs of electrons which supports that it followed octet rule. In addition, all bonds in ethane are single bond.

Methane

Yellow ball=hydrogen atom
Black ball=Carbon atom
Wood stick=polar covalent bond

Methane molecule is shown above and the formula for the Methane molecule is CH4. As the photograph shows, four hydrogen atoms are single bonded to carbon atom and each bond has angle of 109.5 degree. The bonds satisfies octet rule for carbon atom as well as duet rule for hydrogen atoms. The overall structure of the methane is tetrahedral structure because the tetrahedral arrangement of electron pairs produces a tetrahedral arrangement of hydrogen atoms and thus, the structure of methane is tetrahedron. In addition, it cannot be trigonal pyramid because it has a tetrahedral arrangement of electron pairs and as well as a tetrahedral arrangement of atoms.

Ammonia

Sky blue ball=nitrogen atom
Yellow ball=hydrogen ball
Wood stick=polar covalent bond
Ammonia is on the photograph and its molecule formula is NH3.The ammonia molecule has a shape that has three hydrogen atoms connecting one nitrogen atom in a single bond and as a result, there is one lone pair in nitrogen atom to fulfill octet rule. The ammonia molecule also has a tetrahedral arrangement of election pairs but not a tetrahedral arrangement of atoms. It's structure could be tetrahedron but since hydrogen atoms in the molecule occupy only three corners of the tetrahedron, the structure of ammonia molecule is trigonal pyramid.

Carbon Dioxide

Black ball=carbon atom
Red ball=oxygen atom
Spring=polar covalent bond
A carbon dioxide molecule with formula CO2 is shown above and as you can see, there are double bond that connects two oxygen atom to one carbon atom. Also, the diagram shows that the carbon dioxide molecule is a linear structure that has a 180 degree bond angle where two double bonds are at 180 degree from each other. In addition, there are two lone pairs in each oxygen atom to satisfy octet rule.
However, scientific research has shown that there are more possibilities of carbon dioxide molecule shape. For example, there could be triple bond in left oxygen atom that connects center carbon atom and another oxygen atom can connect center carbon molecule with a single bond (OΞC-O). Therefore, there really are 3 structure for carbon dioxide in total so the photograph above is merely one of them.

Water

Red ball=oxygen atom
Yellow ball=hydrogen atom
Wood stick=polar covalent bond
The "stuff" in the photograph is called water molecule and its formula is H2O. The water molecule has a structure of bent or V-Shape although the placement of the 4 electron pairs seems to purpose water molecule as a tetrahedral. However, it still is bent or V- shape because although the placement of the electron pairs determines the structure, the name is based on the positions of the atoms. Thus, it is incorrect to say that the water molecule is tetrahedral. It has a tetrahedral arrangement of electron pairs but not a tetrahedral arrangement of atoms.
The water molecule contains oxygen atom and two hydrogen atoms and the single bond connects two hydrogen to oxygen atom in order to satisfy duet rule for hydrogen atom and octet rule for oxygen atom. There is 2 lone pairs which causes the water molecule to form in bent or V- shape structure. In addition, the angle between electron pairs is 109.5 degree.

Nitrogen

Sky blue ball=Nitrogen atom
Spring=covalent bond
Nitrogen molecule has a formula of N2 where 2 nitrogen atoms are connected in triple bond which are covalent bond in which three pairs of electrons are shared by two atoms. Also, there is one lone pair in each atom to satisfy octet rule. The nitrogen molecule is in a linear structure where two atoms in a line which mean there is a 180 degree bond angle in nitrogen molecule. In addition, the structure of nitrogen molecule in Lewis structure can be written as :N Ξ N:

Oxygen

Red ball=Oxygen atom
Springs=covalent bonds
The photograph above shows the oxygen molecule that contains two oxygen atom and two covalent bonds. The formula for oxygen molecule can be written as O2. Oxygen molecule is bonded in a linear structure where two atoms are at 180 degree from each other. Also, the photograph shows that the oxygen molecule followed the octet rule based on Lewis structure by forming double bonds between two oxygen atoms and making 2 lone pairs in each atom.

Hydrogen

Yellow ball=hydrogen atom

Wood stick=covalent bond

This photograph shows Hydrogen molecule with its formula, H2. H2 molecule contains 2 hydrogen atoms and they are covalent bonded which means they equally share electrons each other. Hydrogen molecule has a linear structure with a 180 degree bond angle. Furthermore, hydrogen atoms are arranged at 180 degree from each other in order to maximize their separation. In addition, hydrogen molecule follows a duet rule and thus, the bond between 2 hydrogen atoms is in a single bond so that each atom can fill up its highest principal energy level to 2.