Saturday, February 26, 2011
Atomic calculation
For around 3 centuries ago, scientist of the world has agreed to use hydrongen's mass as the calculation for all the atomic mass.
Thursday, February 10, 2011
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You gotta be exposed to terms like outermost shells, cation, anion, oxidation, reducing agent all this terms because I know teacher is not gonna repeat. I'll be using such terms from my next post onwards so prepare yourself. Starting will be a little difficult but once you get used to it you will find it quite easy to comprehend.
H2SO4 is sulfuric acid
HCl is hydrochloric acid
NH3 is ammonia
NH4 is ammonium
Etc and Etc.
The compounds with the name that ends with ide are anions.
During the holidays I will post relative masses of atoms and molecules. It's not an easy chapter so yeah read up before I even start anything!! Goodluck for your test I've done what I can(:
H2SO4 is sulfuric acid
HCl is hydrochloric acid
NH3 is ammonia
NH4 is ammonium
Etc and Etc.
The compounds with the name that ends with ide are anions.
During the holidays I will post relative masses of atoms and molecules. It's not an easy chapter so yeah read up before I even start anything!! Goodluck for your test I've done what I can(:
Physical properties of ionic vs covalent substances
From this point onwards I'm gonna use chemical symbols because you must be exposed to it in order to improve your chemistry.
1. Melting and Boiling point
Ionic compound- For instance, sodium chloride melts and boils at very high temperatures or we can call it extreme temperatures. This is because the bonds are relativly strong thus it is hard to break them. A super strong heat is needed to break their molecule force.
Covalent compound- For instance, Hydrogen oxide(h2o) has a low boiling and melting points. This means that the bond within the molecules are weak so they can easily be changed into gaseous state or solid states.
2. Volatility
Ionic compound- The bonds within each molecules are strong so it is difficult for the molecules to break up. That is why usually ionic compound exist in solid states, and why there's no smell from them.
Covalent compound- The bonds within each molecules are weak so little heat energy is needed to break their bonds within the molecules. That is why usually we can smell the sweet perfumes.
Volatile are substances that can be evaporated easily. Such example would be Hydrogen oxide.
non-volatile are substances that cannot be evaporated easily. Such example would be Sodium Chloride.
3. Electrical Conductivity
Ionic compound- They do not conduct electricity in solid states because the ions are not moving. They do not have enough energy to move about in solid state. Only when in liquid or dissolve in water can conduct electricity because their ions can move more freely in liquid states.
Covalent compound- They do not conduct electricity at all because they are sharing electrons not transfering electrons. Covalent compounds do not have ions so current cannot flow. If you're taking physics you can ask me. People taking biology don't have to know why.
4. Solubility
Ionic compound- Some can dissolve in water. Sodium chloride can be found in salt waters.
Covalent compound- They can be dissolve in organic solvent but not water. This is biology now wahaha. Example, there are such thing called tringlyceride that can be dissolved in human fats to provide energy.
1. Melting and Boiling point
Ionic compound- For instance, sodium chloride melts and boils at very high temperatures or we can call it extreme temperatures. This is because the bonds are relativly strong thus it is hard to break them. A super strong heat is needed to break their molecule force.
Covalent compound- For instance, Hydrogen oxide(h2o) has a low boiling and melting points. This means that the bond within the molecules are weak so they can easily be changed into gaseous state or solid states.
2. Volatility
Ionic compound- The bonds within each molecules are strong so it is difficult for the molecules to break up. That is why usually ionic compound exist in solid states, and why there's no smell from them.
Covalent compound- The bonds within each molecules are weak so little heat energy is needed to break their bonds within the molecules. That is why usually we can smell the sweet perfumes.
Volatile are substances that can be evaporated easily. Such example would be Hydrogen oxide.
non-volatile are substances that cannot be evaporated easily. Such example would be Sodium Chloride.
3. Electrical Conductivity
Ionic compound- They do not conduct electricity in solid states because the ions are not moving. They do not have enough energy to move about in solid state. Only when in liquid or dissolve in water can conduct electricity because their ions can move more freely in liquid states.
Covalent compound- They do not conduct electricity at all because they are sharing electrons not transfering electrons. Covalent compounds do not have ions so current cannot flow. If you're taking physics you can ask me. People taking biology don't have to know why.
4. Solubility
Ionic compound- Some can dissolve in water. Sodium chloride can be found in salt waters.
Covalent compound- They can be dissolve in organic solvent but not water. This is biology now wahaha. Example, there are such thing called tringlyceride that can be dissolved in human fats to provide energy.
Wednesday, February 9, 2011
Ionic bonding
http://www.youtube.com/watch?v=xTx_DWboEVs&feature=related
This can be a short introductory to ionic bonding. Okay the electron configuration drawing are shit so don't copy it.
Ionic bonding is the transfer of electrons from an element to another element. Ions are formed when an atom loses or gain electron(s).
A positive ion(cation) is formed when an atom loses it's outer shell electrons to have a fully filled outermost shell.
A negative ion(anion) is formed when an atom gain electrons to have a fully filled outermost shell.
Formation of ionic bonds
One example of ionic bonding can be .... sodium chlroride. A sodium atom would lose one of it's valence electrons to form anion because it has only 1 electrons in it's outermost shell. A chlorine atom would then receive the electron to have a fully filled outermost shell. In this way both of the atoms have fully filled outermost shell which means they are stable but under one condition that is they have to bond together. Initially by itself a sodium atom is Na+ and chlorine would be Cl- . Final result would be NaCl. The forces between them is very strong. This force that is between them are called electrostatic force.
if you want more examples ask me personally. I can't draw out in blogs sorry yeah.
Formation of covalent bonds
Covalent bonding means the sharing of electrons like mrs ow had said. There are single bond. Double bond. Triple bond.
Single bond is the sharing of a pair of electrons
Double bond is the sharing of 2 pairs of electrons
Triple bond is the sharing of 3 pairs of electrons
Covalent bond can only be formed in non-metals group.
For instance, a hydrogen atom has 1 outer electrons and it wants to have a fully filled outermost shell. So, it will share with another hydrogen atom to have a fully filled outermost shell. In this case they share a pair of electrons. So you roughly get the idea of double and triple bond. I couldn't draw it out sorry yeah. Ask me personally if you wanna learn more.
This can be a short introductory to ionic bonding. Okay the electron configuration drawing are shit so don't copy it.
Ionic bonding is the transfer of electrons from an element to another element. Ions are formed when an atom loses or gain electron(s).
A positive ion(cation) is formed when an atom loses it's outer shell electrons to have a fully filled outermost shell.
A negative ion(anion) is formed when an atom gain electrons to have a fully filled outermost shell.
Formation of ionic bonds
One example of ionic bonding can be .... sodium chlroride. A sodium atom would lose one of it's valence electrons to form anion because it has only 1 electrons in it's outermost shell. A chlorine atom would then receive the electron to have a fully filled outermost shell. In this way both of the atoms have fully filled outermost shell which means they are stable but under one condition that is they have to bond together. Initially by itself a sodium atom is Na+ and chlorine would be Cl- . Final result would be NaCl. The forces between them is very strong. This force that is between them are called electrostatic force.
if you want more examples ask me personally. I can't draw out in blogs sorry yeah.
Formation of covalent bonds
Covalent bonding means the sharing of electrons like mrs ow had said. There are single bond. Double bond. Triple bond.
Single bond is the sharing of a pair of electrons
Double bond is the sharing of 2 pairs of electrons
Triple bond is the sharing of 3 pairs of electrons
Covalent bond can only be formed in non-metals group.
For instance, a hydrogen atom has 1 outer electrons and it wants to have a fully filled outermost shell. So, it will share with another hydrogen atom to have a fully filled outermost shell. In this case they share a pair of electrons. So you roughly get the idea of double and triple bond. I couldn't draw it out sorry yeah. Ask me personally if you wanna learn more.
Type of bonding
There are three types of bonding(combine chem only need to know two)
1. Metallic bonding
2. Ionic bonding
3. Covalent bonding
Metallic bonds for combine chem don't have to know you wanna know can ask me via facebook.
1. Metallic bonding
2. Ionic bonding
3. Covalent bonding
Metallic bonds for combine chem don't have to know you wanna know can ask me via facebook.
Revision
Alright I know lots of you get confused with isotopes. They have different number of neutrons not protons.
The valence shell electrons can be determined by their group. For instance, carbon has 4 outer electrons in it's outermost shell so it will be in group4. Group 4 are unique elements. They can decide to whether give or take electrons.
The number of shells can be determined by their period. Carbon has 2 shells so it will be in period 2.
The valence shell electrons can be determined by their group. For instance, carbon has 4 outer electrons in it's outermost shell so it will be in group4. Group 4 are unique elements. They can decide to whether give or take electrons.
The number of shells can be determined by their period. Carbon has 2 shells so it will be in period 2.
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One thing to clarify before I continue.. I'm not a teacher I'm a student like you so I won't get all the answers right.
Tuesday, February 8, 2011
atomic structure
Alright someone requested this to be up so yeah prioty first for those who wanna learn :D
Atomic structure. An atom is made up of subatomic particles. It is the nucleon, proton and electron. The proton number which is at the bottom of the element determines the number of proton and electron number since proton=electron and it is electrically neutral.
The Nucleus of an atom is made up of nucleon and proton. To find proton you can simply use the nucleon number(mass number) to minus off the proton number.
All atoms are electrically neutral BECAUSE their electrons the negative charge(anion) neutrallise with protons the positive charge(cation).
Recap on my previous post on compounds. First shell can hold up to 2 electrons. Second and Third shell can hold up to 8 shells. For instance, Carbon's proton number is 6, so the electric configuration would be 2.4 which means it needs 4 more electrons to have a fully filled outermost shell to gain the stability the atom desire.
Electrons revolves around the orbit of an atom. Electrons have super high energies because they are the most 'excited' particle can be found on man kind this era.
The outermost shell electrons are called valence electrons or simply outer electrons.
Electronic stucture can be easily identified by the periodic table. Verticle sets that is running down the periodic table is called group. The groups determine the number of electrons at their outermost shell. The horizontal row which is running right side is known as period. The period will determine the number of shells.
Sodium and potassium for example. NA(2.8.1) K(2.8.8.1) both are from the same group but different period. So you can see NA has 3 shells and 1 outer electrons so it is in group 1 period 3. Potassium would have 4 shells and 1 outer electrons so it is in group 1 period 4.
I believe I had revised this before.. But no matter I'll revise again.
A metal atom would lose their valence electrons to non-metal to become a noble configuration. This is called ionic bonding. Ions are atoms that loses are gains electrons. Metals transfer their valence electrons to form a positive ion because their proton number is higher than electron number. Non-metals would receive valence electrons to form a negative ion because their proton number is lower than electron number.
This is called ionic theory and it is very important. It will be used in physics and biology.
Atomic structure. An atom is made up of subatomic particles. It is the nucleon, proton and electron. The proton number which is at the bottom of the element determines the number of proton and electron number since proton=electron and it is electrically neutral.
The Nucleus of an atom is made up of nucleon and proton. To find proton you can simply use the nucleon number(mass number) to minus off the proton number.
All atoms are electrically neutral BECAUSE their electrons the negative charge(anion) neutrallise with protons the positive charge(cation).
Recap on my previous post on compounds. First shell can hold up to 2 electrons. Second and Third shell can hold up to 8 shells. For instance, Carbon's proton number is 6, so the electric configuration would be 2.4 which means it needs 4 more electrons to have a fully filled outermost shell to gain the stability the atom desire.
Electrons revolves around the orbit of an atom. Electrons have super high energies because they are the most 'excited' particle can be found on man kind this era.
The outermost shell electrons are called valence electrons or simply outer electrons.
Electronic stucture can be easily identified by the periodic table. Verticle sets that is running down the periodic table is called group. The groups determine the number of electrons at their outermost shell. The horizontal row which is running right side is known as period. The period will determine the number of shells.
Sodium and potassium for example. NA(2.8.1) K(2.8.8.1) both are from the same group but different period. So you can see NA has 3 shells and 1 outer electrons so it is in group 1 period 3. Potassium would have 4 shells and 1 outer electrons so it is in group 1 period 4.
I believe I had revised this before.. But no matter I'll revise again.
A metal atom would lose their valence electrons to non-metal to become a noble configuration. This is called ionic bonding. Ions are atoms that loses are gains electrons. Metals transfer their valence electrons to form a positive ion because their proton number is higher than electron number. Non-metals would receive valence electrons to form a negative ion because their proton number is lower than electron number.
This is called ionic theory and it is very important. It will be used in physics and biology.
Saturday, February 5, 2011
Properties of matter vs. properties of particles
We must not confuse the properties between matter and particles.
Three ways
1. The matter may be coloured but the particles are not. It is due the the wavelength produced by the particles when it is vibrating give the colour. Now I'm teaching physics lol. Different colours travels at different speed. That is why particles vibrate at different speed to give different colours. THIS HAS NOTHING TO DO WITH THE CHANGES IN STATE OF MATTER.
2. The substance that we feel hot or cold doesn't mean that the particles are hot or cold. This is because the speed that the particles have high energy that is why the particles are hot. If the particles have low energy it will be cold.
3. Whenever matter expands, the particles of the matter only increases it doesn't expand.
Three ways
1. The matter may be coloured but the particles are not. It is due the the wavelength produced by the particles when it is vibrating give the colour. Now I'm teaching physics lol. Different colours travels at different speed. That is why particles vibrate at different speed to give different colours. THIS HAS NOTHING TO DO WITH THE CHANGES IN STATE OF MATTER.
2. The substance that we feel hot or cold doesn't mean that the particles are hot or cold. This is because the speed that the particles have high energy that is why the particles are hot. If the particles have low energy it will be cold.
3. Whenever matter expands, the particles of the matter only increases it doesn't expand.
Theory of Matter
Modern Scientist believe that every living and non-living things are made up of tiny particles that are too small too be seen directly. This ideal is known as kinectic particle theory of matter.
There are spaces between particles of matter; the amount of spaces between particles is different in solid, liquid and gaseous.
The particles of matter are in constant motion; particles moves at different speed at different states.
There are spaces between particles of matter; the amount of spaces between particles is different in solid, liquid and gaseous.
The particles of matter are in constant motion; particles moves at different speed at different states.
States of matter
I believe you have learned the states in primary school.. However now secondary level you will evolve deeper.
States of matter:
solid
liquid
gaseous
Characteristics:
SOLID
Has definite shape
Has definite volume
Cannot be compressed
Molecules can only vibrate about at fixed position
LIQUID
No definite shape
Has definite volume
Cannot be compressed
Molecules can flow around easily.
Gaseous
No definite shape
No definite volume
Can be compressed
Molecules has high energy to move about in a container.
if you wanna learn about plasma you can ask me via facebook.
States of matter:
solid
liquid
gaseous
Characteristics:
SOLID
Has definite shape
Has definite volume
Cannot be compressed
Molecules can only vibrate about at fixed position
LIQUID
No definite shape
Has definite volume
Cannot be compressed
Molecules can flow around easily.
Gaseous
No definite shape
No definite volume
Can be compressed
Molecules has high energy to move about in a container.
Friday, February 4, 2011
websites
you can go to this website for further details. if really don't understand can find me I'm free.
http://chemistry.about.com/od/chemistrystudentfaqs/f/bondtypes.htm jyjy !
http://www.authorstream.com/Presentation/WoodRock-37270-elements-compounds-mixtures-Matter-Fact-Why-isnt-good-idea-classify-phase-as-Education-ppt-powerpoint/ << from friend de.
http://chemistry.about.com/od/chemistrystudentfaqs/f/bondtypes.htm jyjy !
http://www.authorstream.com/Presentation/WoodRock-37270-elements-compounds-mixtures-Matter-Fact-Why-isnt-good-idea-classify-phase-as-Education-ppt-powerpoint/ << from friend de.
add in to compounds
picture source
Just for fun xD
Isotopes
What is an isotopes?
Isotopes are atom than have the same atomic number but different atomic mass. This means that the neutron number is not that same as the original atom. example, Hydrogen has 1 proton and 1 electron(number of proton=number of electron) and 0 neutron. it is called hydrogen-1(protium). there is also hydrogen-2(deuterium) and hydrogen-3(tritium). Deuterium has 1 neutron. Tritium has 2 neutrons.
The number of neutrons affect only the physical properties.
some isotopes has names. okay.. one more example from my own contextual knowledge.
carbon-12 the normal one carbon-13 gained 1 extra neutron and carbon-14 gained 2 extra neutron.
carbon-14 is used to find out the age of an ancient object. the more reactive it is the older the object is. It is called radiocarbon dating.(can be found in your textbook)
carbon-13 is used to find out the wavelength of noises underwater.
both of this are natural. there are man-made isotopes too. beware that carbon-14 is highly radioactive.
Mixture
Note that Mixtures can be a element to element, element to compound or compound to compound. Quite confusing but hope you can digest it.
Next, how is a mixture form? A mixture is formed when a solute dissolves in a solvent. A solute is the substance that dissolve in solvent and solvent is the liquid that solute dissolves in.
There are three types of mixtures(secondary level only needs to know solution and suspension).
Solution- the solute can completely dissolve in the solvent.
Colloids- particles are completely seperated evenly in the solvent but not dissolved.
Suspension-particles are unable to dissolve thus will eventually drop to the bottom.
There are three types of solutions
1. dilute-weak concentration of a solution.
2. concentrated-moderate concentration of a solution.
3. saturated-maximum concentration of a solution.
Suspension are formed because the ideal particles are unable to dissolve in a particular solvent.
For example.. sulfur cannot dissolve in water thus forming a suspension.
However sulfur can be dissolved in methylbenzene(yes extracted from test paper).
what's the explanations for this?
Very simple. The particles are too big to be dissolved in water but it is just right to be dissolved in methylbenzene(CH3). In this case, salt(NaCl) can be dissolve in both water and methylbenzene(not really good).
Okay.. what else...
Oh yeah. how do you know which one is a suspension which one is a solution?
A solution is homogenous(uniform throughout), no residue is found and no seperation when left to stand. A suspension is the opposite of a solution.
Continued~
The Video you can look at it when you're bored just to make the atmosphere feel better~ we're all students so I understand when teacher doesn't give us break LOL hahahas.
Compound
Compound have different properties as of their element root. What is element root?
CO2 - carbon dioxide Carbon and oxygen is the root of the compound. It is not tested in syllabus but is good to know.
For example Oxygen is combustable and Carbon is used to strengthen the molecule to make the substance harder. However the compund is not combustable and it's a stable molecule by it's own unlike carbon and oxygen.
Maybe you're wandering why elements chemically combine? Quite troublesome huh?
Because they want to be more stable. Alone by itself an atom is not chemically stable because their valence shell or you can call it outermost shell is not fully filled with electron. For instance, Carbon's electronic configuration is 2.4 because it has 6 electron. First shell can only take up to two electrons. The Second and Third can be filled up to 8. because the outermost shell is still lack of 4 electrons it will want to chemically combine with another atom to form a stable particle. You maybe wandering STILL why Carbon combine with two oxygen instead of one is because oxygen's outermost shell has 6 electrons(2.6) and it needs 2 more electrons to form a stable particle. The Carbon would then give up 2 of it electrons to one oxygen atom and other 2 to another oxygen atom thus fully filling their outermost shell to form a stable particle known as Carbon dioxide(CO2).
The chemical reaction is called covalent bonding. I'm still not really good at it but I can tell you briefly. Covalent bonding is the sharing of electrons between atoms to form a stable particle. There is also double bond and triple bond. Double bond shares 2 pairs of electron(4electrons) and triple bond shares 3 pairs of electrons(6electrons) << probably at sec 4 pure science would learn combine science don't have to I think.
Examples of compound
NaCl(sodium chloride salt)
H2SO4(sulfate)
HCl(hydrochloride)
this are the more common ones.
Elements
http://www.youtube.com/watch?v=ssaUusY6hWM&feature=related
you can take a look at this.. quite joker lah.
Recap.. Elements are particles made up of only one type of atom.
One type of atom as in single element. Examples are.. H2 O2 so yeah.. when two atom same type of element chemically joined together it is still an element BECAUSE it's only made up of one type of atom. Such particles are called molecules. That means yes all compounds are molecules.
The common ones are
Oxygen(O)
Hydrogen(H)
Chlorine(Cl)
Sodium(Na)
Copper(Cu)
Iron(Fe)
Silver(Ag)
Gold(Au)
Argon(Ar)
Carbon(C)
Potassium(K)
Maybe enough for examples. Those elements are based on my knowledge because I didn't really go and memorize all this. Actually don't have to memorize just need to familaries it.
As you can see most of their symbols take the first letter either from the name or it's latin name.
you can take a look at this.. quite joker lah.
Recap.. Elements are particles made up of only one type of atom.
One type of atom as in single element. Examples are.. H2 O2 so yeah.. when two atom same type of element chemically joined together it is still an element BECAUSE it's only made up of one type of atom. Such particles are called molecules. That means yes all compounds are molecules.
The common ones are
Oxygen(O)
Hydrogen(H)
Chlorine(Cl)
Sodium(Na)
Copper(Cu)
Iron(Fe)
Silver(Ag)
Gold(Au)
Argon(Ar)
Carbon(C)
Potassium(K)
Maybe enough for examples. Those elements are based on my knowledge because I didn't really go and memorize all this. Actually don't have to memorize just need to familaries it.
As you can see most of their symbols take the first letter either from the name or it's latin name.
The Periodic Table History
okay back to the road.
As you can see.. the first one is the table with the pictures. Second one is the more detail one. Sorry couldn't find the table which has name of the elements on it. Leave comment if you don't know what the elements stands for.
For example Carbon.. it's element symbol is C as it takes from the first letter of Carbon. Different element for example Potassium the symbol is K, which is the the first letter of it's latin. So yeah..
Okay.. a little bit more into it. As far as I have studied and research..
Element are particles only made up of one type of atom.
Compound are molecules made up of two or more different type of atoms chemically joined together.
Mixtures are molecules made up of two or more different type of atoms physically joined together.
Note that the difference between Compounds and Mixtures is that one is joined together by chemical means and one is joined by physical means.
Introductory
Welcome to my blog. A little bit intro I'm still schooling. This is some kind of a... you can say that it's a project. Well the main reason for this blog creation was for myself to improve and look through. Maybe it can benefit some other people.
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