Saturday, July 25, 2009

dirt dirt go away

Hey peoples,when guy all bath did you all using soap???
or when your mum washing plates,cloths or floor did she use detergent??
obviously yes right??
do you know haw to process the soap??
let me tell you all by now...
i have done some research from web,i found out the process of soap making...LOL

What is saponification??actually saponification also know as soap making, saponification is the reverse of esterification..

Saponification is usually used to refer to the reaction of a base with a fot or oil to form a soap. Saponifiable substances are those that can be converted into soap.
Sodium hydroxide is a caustic base. If sodium hydroxide is used a hard soap is formed, whereas when potassium hydroxide is used, a soft soap is formed. Vegetable oils and animal fats are fatty esters in the form of triglycerides. The alkali breaks the ester bond and releases the fatty acid salt and glycerol. If necessary, soaps may be precipitated by salting it out with saturated sodium chloride. The saponification value is the amount of base required to saponify a fat sample.
In a laboratory procedure the triglyceride trimyristin is obtained by extracting nutmeg with diethyl ether.Saponification to the sodium salt of myristic acid takes place with NaOH in water. The acid itself can be obtained by adding dilute hydrochloric acid.
example of Ester
Oil and fats + NaOH--> Soap + Glycerol
Glycerol also has the systematic name which is 1,2,3-propanetriol. It is a very important by-product from the soap making industries. Glycerol also used for making cosmeties like lipstick and moisturisers as it has excellent moisturising properties.


Now let me teach you all the step of preparation of soap:
1. 20mL of a 20% weight per volume NaOH solution is mixed with 5mL of any oil.
2. 10mL ethanol is added to aid in the mixing of the reactants.
3. the mixture is boiled using a hot plate on water bath for 30 minutes.
4. water is added periodicaaly to maintain a constant volume.
5. a curd of soap forms on top of the mixture.
6. 5g of solid salt NaCl is added and boiled for a few more minutes.
7. the salt precipitates the soap which floats on top oh the solution as a solid.
8. filter,wash and test the soap.


soap and detergent acts as an emulsifier breaking oil and grease into tiny droplets which can mix with water.grease and oil are non-polar hydrocarbons,however water is polar and so it will not dissolve this non-polar grease or oil.
what is surfactants???
surfactants are lower the surface tension of waterby disrupting hydrogen bonds between water molecules and thus increases its ability to wet a surface.
water does not wet grease very well
water with surfactants like soap or detergents spread out over the grease and wetting it.

soap have a long non-polar rail and a polar anionic head.The non-polar tail is hydrophobic meaning that it is hates water. whereas the polar head is hydrophilic which is like water.
when surfactants are added to water, they do not spread evenly in water,instead they clumo togather as shown.When the surfactants clump togather and stay suspended in water the negative heads point outwards and interact with water molecules by ion-dipole interaction.
the non-polar tail enters into the non-polar grease or oil which means dirt leaving the polar head in the water. the tail dissolve in the grease dirt and the heads dissolve in water drawing water onto the dirt and fabric. as the water is swirled around,it pulls the grease out of the cloth.soap,water and grease togather form an emulsion with the soap acting as an emulsifier,suspending the normally incompatible grease in the water.

differences between soaps and detergents:
-formation
formation of soap is by animal fats and vegetable oils which come from renewable resources
detergent is make by hydrocarbons which come from the petrochemical industry,it is non renewable resources.
-structure
soaps are ionic on polar head with a long,non-polar hydrocarbon tail. soap are anionic.
detergents have same structure to soap ionic head and non polar tail,but detergent can be anionic,cationic or non-ionic.
-manufacture
soaps are manufacture by saponification,heating fats or oils whic are esters with NaOH or KOH,then precipitate with NaCl
one example of detergent is propene from petrochemical industry polymerises into polyprope,it also adding of a benzene ring.detergent also reacting with H2SO4 and also reacting with NaOH to form sodium sulfate.
-reaction with hard water
soap do not lather well in hard water,soaps will form scum with calcium and magnesium this will cause the clothes dull and grey
detergent will lather in hard water,detergents do not precipitate mineral salt in hard water.
-biodegradability
soaps are biodegradeble
detergents are biodegradable if hydrocarbon chain is straignt,while non-biodegradable if is branched chain.
-phosphates
soaps do not contain phosphates
detergents may be mixed with phosphates which pollute the enciroment
Soap and detergent reli helpfull enough,use it everyday to keep ur stuff clean always and delicate frangrance..LOL






Sunday, July 19, 2009

battery reli is usefull enough..hehe

mobile phone: im proud of myself because i can give human being entertain such as provide them songs, sms, video call and etc..
battery : reli??
mobile phone: yea, im great ...
battery: doest u think before how u retain ur life? how u survive??
mobile phone: no, i can live without any help!!!!!
battery: u are wrong, without me u even cannot functioning, im the 1 who help u conserve ur life span...
mobile phone: do not cheat me, i do not believe that i need to rely on u...
battery: please reflect on how u make electrical energy by urself?? without me u cannot produce electric at all..
through the conversation try to ask urself:
can u enjoy ur life without entertain??? such as mobile phone,labtop,mp3 and etc????
what thing make those stuff easily to carry?? bring along ur journey???
tadah!!!!! it is battery...
virtually battery are ubiquitous...we can obtain it easily in any where at any times...
by the way try to imaging that if without battery ur life can be so relaxing and convenient??
for me the answer is no,because without battery many thing cannot functioning well...
otherwise we always need to find the place which have the electric circuit to support our stuff...
like this will bring a lots of troublesm because we need to bring tonnes of thing when goin out....
it's wasted times as well as energy...

now a day scientist invent many type of battery which included dry cell, alkaline cell, silver button cell,lithium iodide battery, lead acid accumulator, nickel cadmium cell, vanadium redox battery, photo voltaic cell and also fuel cell. among all of those cell we can assign them into rechargeble and also non-rechargeble cell..

In electronics, a battery or voltaic cell is a combination of many electrochemical Galvanic cells of similar type to store chemical energy and deliver higher voltage than with single cells.The battery cells create a voltage difference between the terminals of each cell and hence to its combination in battery. When an external electrical circuit is connected to the battery, then the battery drives electrons through the circuit and electrical work is done. Actually battery is a device that converts chemical energy to electrical energy. It consists of one or more voltaic cells, each voltaic cell consists of two half connected in series by a conductive eletrolyte contianing anion and cation.
Now let me introduce you all some rechargeble and non-rechargeble cell and some new technology cell. Let us go through the detail of the cell:
Dry Cell
the cell diagram as below:
Zn(anode reductant)/Zn2+/NH4Cl(electrolyte)/MnO2(oxidant)/Mn2O3,Carbon rod(cathode)
The elctrons are transfer from Zn to MnO2

chemical reaction of dry cell
At anode (oxidation occurs)
Zn(s)----->Zn2+ + 2e-
At cathod reduction occurs
2NH4+ + 2e- -----> 2NH3(g) + H2(g)
2MnO2(s) + H2(g) -----> Mn2O3(s) + H2O(l)
At the electrolyte
Zn2+(aq) + 2NH4Cl(s) + Zn(s) -----> Mn2O3(s) + H2O(l) + Zn(NH3)2Cl2(s)
Usually dry cells is used in toys,touch light,remove control and etc..
Dry cells have many advantages it also bring a lots of disadvantages to us..
-The advantages of dry cell is it is mass produced in factories that why it is very cheap and readily avaible.
-Whereas the disavantages are gasses can accumulate and cause the dry cell to explode and its voltage drops steadily when it is used.
-Dry cell is a non-rechargeble battery and has to to be thrown away one it become flat. This create disposal problem as it contain chemical.
-While as the zinc causing turns into zinc ion,holes from in it,this will cause the chemical inside to leak out.

Lead Acid Accumulator
The cell diagram as below
Pb(anode)/PbSO4/H2SO4/PbO2/PbSO4,Pb(cathode)

Chemical reaction of Lead acid accumulator
At anode (pure Pb plate)
Pb(s) + SO4 2- ------>PbSO4(s) + 2e-

At cathode (Pb plate coated with PbO2)
PbO2(s) + H2SO4 + 2e- ----> PbSO4(s) + 2H2O(l)

Overall Reaction
Pb(s) + PbO2(s) + 2H2SO4(aq) -----> 2PbSO4(s) + 2H2O
Lead acid accumulator is used in automobile. It also know as car battery.
The advantages and disadvantages of lead acid accumulator
-The advantages of lead acid accumulator is it is a rechargeble battery because the anode and cathode reaction can converting the cell into an electrolitic cell.
-During discharge means when the battery is used the Pb plate will transfer the electrons to Pb with PbO2,so that Pb plate become PbSO4 while Pb with PbO2 become PbSO4.
-When during recharging Pb plate turned into PbSO4 and PbO2 turned into PbSO4
2PbSO4(s) + 2H2O(l) -----> Pb(s) + PbO2(s) + 2H2SO4(aq)
-However,this recharging can occur only if the lead sulfate adheres to the lead plate.If the lead sulfate has fall down to the sink,the battery cannot be recharge any more.It has to thrown away.
-This battery produces a large current and the voltage prodecu is nearly constant.
-Whereas the disadvantages is lead acid accumulator is big clumsy heavy and not easy to transport.
-It contains lead a toxic metal which can pollute the enviroment.Therefor this battery should be dispose off carefully.
-If lead reaches the soil it will containminate plants.Other consumers who eat this plant can suffer from lead poisoning.
-The battery also contain quite concentrated sulfuric acid.This is a corrosive liquid and it should also not be allow to reach the enviroment.

Vanadium Redox Battery (new technology cell)
This battery was discovered at the university of New South Wales by a lady called Professional Maria Skyllas Kazacos.
The cell diagram as below
C,V2+(anode)/V3+/H2SO4/VO2 +/VO2+,C(cathode)
Chemical reaction of vanadium redox battery
At anode (oxidation accurs)
V2+ -----> V3+ + e-
At cathode (reduction occurs)
VO2 + + 2H+ + e- -----> VO2+ + H2O(l)
Overall reaction
V2+ + VO2 + + 2H+ ------> V3+ + VO2+ + H2O(l)
Vanadium Redox Battery is a relative new battery which is constantly being improved. It has been used in electric Golf Cart and emergenct back-up battery system in Department of Defense in New South Wales.
The advantages and disadvantages of vanadium redox battery
-The advantage is it contains solution of salt of vanadium which is very easily and cheaply available and it can produce very high current and high voltage.
-The anode and cathode reaction can be reverse easily, therefor it is an 100% efficient rechargeble battery.
-Recharging can be done in two ways:
*by exchanging the electrolytes with fresh one
*by cinverting it to electrolytic cell which reverse the flow of electron
-The electrolyte solutions can be recycle many times,so the electrolytes never need replacing and so there is no wastetage of chemical.
-The electrolytes are all vanadium with difference oxidation number and therefor they never get containminated even they are mix up.
-The battery does not get overheated because the solution act as cooler,so it is a very safe battery.
-Vanadium is non toxic and so cannot polluted the enviroment.Beside, it is recycle and used again and again,so there is no need to dispose it off.
-The disadvantage is vanadium redox battery requires large tanks of the vanadium eelectrolytes,therefor it is clumsy,bulky and heavy.
Bettery can distribute into many type and it bring many advantages and disadvantages to human being,so we must use it in proper way and make sure it wont contaiminated our enviroment..



Monday, July 13, 2009

say NO to cola..


feel thirsty?? let have a can or bottle of coke,help u to quench one's thirst...LOL
cola which is a well known brand of product in the world, for sure that almost all kids or adults also like to drink soft drink...
exspecially me, the cola's admire...
i was get cola addictive since im study secondary school (but always let my parents nagging =.=')
i like cola due to it is cheaper and available in everywhere..
when u having the drink do you will check out what is the ingredient??
im not so clear about the content of cola..
i also feel curious about what make it so tasty??
let me explore it by today..

Buffer..do you know what the purpose of buffer?? actually it can used in beverage bottling..
Buffer is a mixture of a weak acid and the salt of its conjugate base.
Function of buffer is it maintains the pH at a constant eventhough small quantities of an acid or base is added to the buffer the pH does not change..

for buffer it will produce carbonic acid which has the formula H2CO3. It is also a name given to the solution of carbon dioxide in water, which contain small amounts of H2CO3. The salts of carbonic acids are call carbonates, it is a weak acid..
Carbon dioxide dissolved in water is in equilibrium with carbonic acid:
CO2 + H2O ⇌ H2CO3

Carbonic acid which produce through the buffer is used in making fizzy drink like cola.
the CO2 inside the water and carbonic acid is equilibrium, this make cola has a sharp taste and also fizzy gas, make the drink more tasty..

let go through the ingredient of coke, i found out that the soft drink we have drink consist of many harmfull chemical that will effect our body..reli is a bad news for me,since everyone ask me to control..i cannot stand for without coke,so sad..XD
now im going to elaborate the ingredients of cola as below:

-sugar

cola consist of sugar it's for sure due to it taste sweet,yet,a can of coke contain too many sugar approximately 10 teaspoon of sugar which is exceed our body needed..GOSH!! seem like taking the sugar and eating more than drinking..

Sugar, granulatedNutritional value per 100 g (3.5 oz)
Energy 390 kcal 1620 kJ
Carbohydrates
99.98 g
- Sugars 99.91 g
-
Dietary fiber 0 g
Fat
0 g
Protein
0 g
Water
0.03 g
Riboflavin (Vit. B2) 0.019 mg
1%
Calcium 1 mg
0%
Iron 0.01 mg
0%
Potassium 2 mg
0%
Percentages are relative to US
recommendations for adults.
According to this list we can notice that the main nutrient of sugar is carbohydrate, if consume too many carbohydrate will bring a lots of negetive effect to us, such as tooth decay, diabetes, obesity, gout and cancer and etc..

-caffeine

Caffeine is also a common ingredient of cola, originally prepared from kola nuts. Soft drinks typically contain about 10 to 50 milligrams of caffeine per serving. Caffeine used to enhance the soda of flavour.
Caffeine binds to receptors on the surface of heart muscle cells which leads to an increase in the level of cAMP inside the cells, it also will stimulate the nervous system and the increases heart rate.

-artificial sweetener
sugar substitute is a food additive that duplicates the effect of sugar in taste, but usually it has less food energy. Some sugar substitutes are natural and some are synthetic. In general those are not natural are referred to as artificial sweeteners.
if increased consumption of coke which contain of artificial sweeteners can cause body weight gain and obesity.
-acid



phosphoric acid is used to acidify foods and beverages such as cola, it provides a tangy and sour taste for cola. It also being a mass produced chemical, is available cheaply and in large quantities. The low cost and bulk availability is unlike more expensive natural seasonings that give comparable flavors.
drinking cola will result the skeleton effect because it contain of phoshoric acid which will leads to lower bone density.it also will cause headache and imflammation.

-Sodium
Sodium benzoate has the chemical formula NaC6H5CO2. Sodium benzoate act as a preservative in and stablizing agents cola and it is fungistatic under acidic conditions.it will cause high pressure and the person whose have asthma will get allergy after consuming sodium benzoate.

-carbon dioxide

carbon dioxide is an anhydride of the carbonic acid, it is also a good solvent which can reduce the amount of caffeine inside the drink.carbon dioxide has a sharp and acidic adour which can make the cola more tasty.it can produce a sour taste in mouth and stinging sensation in the nose and throat.

carbon dioxide is very toxic,a little of carbon dioxide about 1% will cause increased blood pressure and pulse rate,it also will reducing hearing. if about 5% it will causes difficulty in breathing accompanied by headache and shortness of breath. if more than 5% it will make us sweating, headache and dim vision.

-preservative,coloring and flavouring
preservative is a natural or synthatic chemical which added in cola to maintain the colour and taste of the drinks. the preservative can cause respiratory or other health problem of human like coma.coloring and flavouring are used to make the drinks look more attractive and more tasty,by the way the coloring and flavouringalso will bring the negative effect to our body such as allergy.

Carbonated beverage consumption has been linked with diabetes, hypertension, and kidney stones, all risk factors for chronic kidney disease. Cola beverages, in particular, contain phosphoric acid and have been associated with urinary changes that promote kidney stones. Drinking 2 or more colas per day was associated with increased risk of chronic kidney disease.
after knowing the ingredients of cola we can realise that cola does not bring any advantages to human, yet it just will cause human getting many diseases. for ur own good do not consume too many soft drinks as you can.Please say NO to cola...LOL

Tuesday, July 7, 2009

EVIL acid rain..=X

krong... krong... krong....
sky turning darkness...

wind blow strongly..
thunder shooting...


rain is coming...
this is the natural phenomenon of raining...

lol..let's get back to our main topic..
actually the main point of having this post is wan to talk about formation of acid rain..
hw acid rain have been form?? it is cause by???

Pure rain water in unpolluted areas have pH of about 5.6 which is weakly acid because the atmosphere contains of carbon dioxide an acidic oxide.
H2O (l) + CO2 (g) → H2CO3 (aq) → H+ + HCO3− (aq)

As years gone by, the countries are become more progress...
many industries are growing..this cause the atmosphere have been polluted..
at certain parts, exspecially highly industrialised areas, the pH can be even lower than 5.6 this is acid rain...


Acid rain is caused by a few factors, example:
-Burning of fossil fuels like coal, petroleum which contains sulfur as impurity.
S (s) + O2 (g) → SO2 (g)
-Smelting of ores like sulfide ores
2ZnS (s) + 3O2 (g) → 2ZnO (s) + 2SO2 (g)
-Hot vehicle engines exspecially when traffic jam produce NO2(g) an acidic oxide
N2 (g) + O2 (g) → 2NO (g)
2NO (g) + O2 (g) → 2NO2 (g)
-Even during lightning also will produce NO2 (g)
N2 (g) + O2 (g) → 2NO (g)
2NO (g) + O2 (g) → 2NO2 (g)
-Hot incinerators, furnaces also produce NO2 (g)
-Soil bacteria can also release NO2 (g) from nitrogeneous matter in soil.
-increased use of fertilisers also contribute release of NO2 (g) to the atmosphere.

From burning fossil fuels and smelting ores we get SO2 (g). When SO2 (g) added with oxygen we will get sulfur trioxide which is an acidic oxide. When it rains, all these acidic oxides will dissolve in rain water to form acid rain.
Effect of acid rain :
-It cause weathering of rocks which crumble
-Acid rain dissolves important nutrients and removes them from the soil, making them unavailable for plant growth
-Acid rain can displace aluminium and other heavy metals from the soil. These heavy metals are toxic it will make the plants die when there is too much aluminium ions in the soil
-Steel or iron building are attacked by acid rain cause it rusting, so that need to paint the building often
-Marble status are atteacked by acid rain and tend to destroy
-Many tree will loss their leaves due to acid rain, the plant cannot carry out photosynthesis when it loses all ots leaves, so eventually die
-The river will polluted by the acid rain, very low p of water lead the marine animals cannot survive
-Human being with bronchitis and asthma find their condition worsering due to acid rain
for the sake of all peoples good,we need to take some action for decreasing the formation of acid rain...
Controlling of acid rain :
-Those fossil fuel such as coal with a very low sulfur content should be burnt
-All combustion furnaces in factories and industries should have " flue gas desulfurisation" process attached. Scrubbers are used for this desulfuration process. Coal, air and CaCO3 are mixed in the combustion furnace.
S (s) + O2 (g) → SO2 (aq)
CaCO3 (s) → CaO (s) + CO2 (g)
CaO (s) + SO2 (g) → CaCO3 (s)
-All these products enter a scrubber where there is acid and water. CaCO3 turns into CaSO4 which can be used for making plasterboards.
-Minimise the usage of electrocity because electrocity is produce by burning of fossil fuels
-Minimise used of petrol due to this will also produce sulfur dioxide and nitrogen dioxide. We should depent on electric transport or public transport.
Hey guys, for our own good, please cooperate to reduce usega of fossil fuels for preventing form of acid rain~~