essay life style changing

Senin, 23 Mei 2011

LIFESTYLE CHANGING
           
Lifestyle is a word that shows how we endure our life, how we act in this life, how we interact with others and it also means the way we think about every part in our lives. We know that our lifestyle changes every time. Yesterday we still used abacus to do our math homework, but now we just use our calculator or computer to account the numbers. Yesterday we used bicycle to go to other places, and now we use motorcycle and car to reach the places. Our lifestyle is changing from the primitive one in long time ago to a modern lifestyle in this globalization era. But, do you know the last primitive lifestyle gave us some advantages which cannot be given by modern lifestyle. Primitive lifestyle is better than our modern because some aspects which can give us a better life.
            When we think about primitive ethnics like Dayak in Kalimantan, Kubu in Sumatera, and Asmat in Papua, we directly think they are so weird and left behind. They do not want to accept technology which comes to human’s life, they still live in jungle, in short they do not want to mingle with others in this globalization system. On the other hand, when globalization system comes to our life, people change their lifestyle to a modern one which imitated from big countries like America, United Kingdom, China, Japan, and others. They use so much technology to do everything in their lives. They use telephone to communicate, use motor vehicles to transport, and they also use technology to do their house works like washing clothes, cooking food, and cleaning the rooms. Based on this detail, we can decide that a modern lifestyle uses some technology, instead the primitive lifestyle does not want to use even they do not want to know about anything in technology.
            The first reason why primitive lifestyle becomes better than the modern one is about their lives are healthier than our lives, we all know that the food which we consumed are taken from our nature, meat from animals and vegetable from plants. Although the modern or primitive people eat the same source of food, but each other gets the different nutrition. In modern era, the food serves with interesting look, and processed with some essence added to the materials. The past food or usually we call it junk food like pizza, hotdog, and soon are very common in our life. And the strange part is we still eat it although we know that foods are not healthy. Another example, our vegetables and fruits are packed with modern ways, and off course it uses preservative essences that make it looks more interesting. But in primitive lifestyle, they just picked their vegetables and fruits from their own garden and then they cook them with simple ways like frying, boiling, or roasting. It will help them to get full nutrition from that food without adding or subtracting other essence like preservative, food coloring, and other thing to make their food more delicious or get more interesting look. And the other things that make primitive people’s live become healthier is drink. Modern people love to drink some packed product of drink like soft drink, caprice coffee, caprice tea, and other instant drink which are tasted delicious. But, primitive people like to consume fresh water, natural coffee, and some herbal drink that are made by themselves. And with that healthy and natural drinks or food make people’s live better. Comparing our modern food with primitive one, In my opinion we would better consume more natural drink and food than junk food for our health. So, in this side we can see that primitive people is healthier than us.  And if we want to be healthier, just try to consume more natural food.
            As we know, primitive people do not accept the technology that come to our lives. They don’t want to use computer, television,even motorcycle. Because they do not use motorcycle or car, they have to ride the bicycle or they have to go on foot to move and reach other place. In other side, we all the modern people in this globalization era want to have at least one of motorvehicle. We can see people around us, one home has one or more vehicles, and we depend on motorcycles and cars to move from one place to another place. Consequently, when we necessary have to walk down to reach other place without vehicle, we will feel very tired. It happend because we don’t have any desire to walk and we do not feel usual with walking down on the road, we just want to ride motorcycle or drive car. It is different from primitive people, they do not want to use motorcycle or car, so that they have to walk everyday to visit and reach other place. It will help them get healthier because they are doing exercise every day. Primitive people change the sport like basket ball, jogging, and soccer to a simple activity. They walk around to transport and they do it everyday. So, by unknowing  technology like vehicle help primitive people to live healthier than us in this modern era with so much technology.
            We all know that every vehicle especially motorvehcle like car, motorcycle, and other use fuel which is from fosil, and when we turn on and use the vehicle, it will produce some noise and smoke. Vehicle’s smoke is one of the aspect that cause air polution. The air which has been poluted by smoke will cause some bad impacts to our body and our environtment. It causes some illnesses especially in respiration system, and air polution also causes global warming. Another source of polution is an-organic garbage. Motorcycles, cars, computers, washing machines, refrigirators, handphones, televisions, and so many electronic devices will become an-organic garbage. We see that every time the form and model of technology products and electro devices always change. Yesterday we use a big computer, now we use a  small laptop and notebook. Yesterday we use motorcycle, now we use car. Because of human’s nature that we will never feel satisfied, we always want to change our old stuffs to a new one, we want to change our old computer to a new laptop, and then the computer will become garbage which will be thrown away. Imagine if fourty percent of people in this world do the samething, how many computer garbage will be collected? This garbage will causes land polution because an-organic garbage can’t be coated. Primitive people don’t use motorvehicles so that they will not get illness and,free from polution, and get healthier. Other advantage, because they don’t use technology they don’t need to throw the electro devices garbage away, and it will chase the polution. Primitive people’s lifestyle become healthier and better than modern people’s lifestyle because they dont know about technology.
            Globalization means every part in life has become worldwide. The example of gllbalization are economic globalization, cultural globalization, lifestyle globalization, and so many aspects of life that has been globalize. Everything in our life has been influenced by other countries because of this globalization era. We are free to get information about other country’s culture, we can see American people’s lifestyle, we can eat Japanesse people’s food, and we can imitate French people’s fashion because of globalization. But, the globalization system doesn’t influence primitive etnic’s live. They don’t use technology so that they can not see what happend in Malaysia, what happend about Egipt’s political case, even may be they don’t know about Gayus case. Althought there is no technology in their live and it will let them left behind others, they feel comfortable with that. It happend because they get advantages from unknowing anything about globalization.
            Technology and globalization make our life become easier, one of the advantages which brings by technology is we can get more information and news from every part of country in this world. Development of technology in information and communication parts produce some mass media like television, telephone, internet, radio, and others gives us news and information everytime and everywhere. But, do you  know news and information that gives by technology sometimes tell us to leave and reduce the use of technology itself. For example, there are so many news that tell us to consume more natural fruits and less preserved fruits, do more exercise like bicycling and jogging than use vehicles, and the other one is keep continuing our own culture. Culture is one of some aspects which can be ruined by technology and globalization. As we know our lovely country Indonesia has so many different ethnics and culture. We can find many kind of regional languages, traditional clothes, traditional songs, traditional dances, traditional houses and some traditional ceremony and also religion from Sabang to Merauke. As Indonesians we all proud of these differences and we really understood the word ‘Bhineka Tunggal Ika’. But, since globalization and technology come to Indonesia, people change their perception. They are starting to leave their own culture and try to imitate other country’s culture like America, Japan, China, Korea, and French. Basically the changing of people perception started from information and news that serve by technology. We can see American people’s clothes, culture, and lifestyle from internet and television, and then people in Indonesia start to imitate it and make it become a trend center, finally people leave their own culture. For Muslim people, we know that the American style is not match with our religion and culture, but some teenagers have been influenced by this common style. They love to wear jeans and T-shirt to go to mosque when they actually should use Baju kurung or baju koko. It is very vital when Indonesian people give more love to foreign culture then our own culture. E
            Even thought almost of Indonesian people start to leave their pattern culture, do not forget about Indonesian primitive ethnics people. As we know, primitive people do not use any kind of technology, so they do not know about America, Japan, and even Jakarta and other Indonesia’s big country. Because of that case, they are not influenced by globalization. And they still continue their own culture without some interference. We have to thank primitive peoples because they still continuing their culture which is one of Indonesian culture too, and hopefully our country do not loose these cultures and still have the characteristics of Indonesia as cultural country. Primitive people still wearing their traditional clothes, doing traditional ceremony, and produce some handcrafts and art productions. I think primitive people can defend their culture as long as they do not know and influence by technology and globalization. We are as modern people also have to remain our own culture like primitive people do, we can remain it with carefully choosing the information and news from other country which have influence to our live, and do not imitate the culture which not appropriate with our pattern culture. I hope our culture can be preserved and Indonesia does not lose its own characteristic.
            Another aspect that can make primitive people life become better than our modern lifestyle is about interaction and communication. We know that as human being we cannot live alone in this world. We need other person to fulfill our needs like farmer to farm our foods, we need friends to share our opinions and experiences, we need entertainer to cheer our life, and absolutely we need parents to give us life and teach us how to undergo our own life. Because we need other person to contribute in our live, we need to master the key of relationship which are interaction and communication.
            Interaction and communication are the important part of our life. Without interaction and communication, we cannot ask someone to help us, we cannot buy something to our daily needs, and we cannot learn about everything because learning needs communication. In this modern era, globalization system has been running in every part of the globe, so that we also need to interact not only with our neighbors or local people but also with other citizens in other country. Because of the need of communication, people start to create some invention in communication technology. Nowadays, we have known some technology tools in communication like television, internet, social network, facebook, e-mail, and other common things. As modern people in globalization era we need these tools to interact and communicate with other people especially in distance area, but we do not need this tool to communicate with our neighbors and our friends, what happened now? Everyone especially teenagers use these tools to communicate with other although they can do the direct interaction. On the other side, primitive people do not use these kinds of tools to interact and communicate because their populations are isolated from other. They do not need to interact with foreigner people from other country because they do not put themselves at interface of globalization, they just talking and communicating with their neighbors so that they do not use telephone or internet to communicate with others, and I think without technology primitive people get some advantages for their live.
            Primitive people do not use technology to communicate, so that they have to do communication and interaction with the basic way which is face to face one. Face to face, it means that people meet each other to communicate and talk directly to the person. And we know that face to face interaction is the best way to communicate because we can easily understand what people want to say through their face. But, I think in this modern lifestyle people rarely communicate with direct way, we just use technology like telephone, cell phone, e-mail, facebook, and other media to interact with others. May be need these media but we can limit the using of technology, just use it when we really need it. For example facebook, which is one of common communication media that used by people to interact with others. We all know that facebook has some negative effect which can ruin our live. Nowadays almost everybody has one of facebook account and they use it every time, they chat with other people trough facebook every day, they share their experiences and opinions trough facebook, even they still use facebook account when they are working. It happened because of some reasons like they use it for working, they use it for communicate with friends, or they use it just for fun. But these online activity can cause some impact to their live like when they work in front of computer every day it can causes some disturbance on their vision because the radiation, other impact is the feeling of dependence to facebook because they want to share and tell their opinion and experience every time, the last impact is they do not want to interact directly face to face with other people because they just use media to communicate. When technology has been developing, people start to refuse and reduce direct communication in their life, they just want to use technology to interact with other because they think it is simple and cool, but when it becomes the behavior it will causes trouble when they forced to do face to face communication. For example a man who use technology to interact in his daily live has forced to give a presentation at a meeting, presentation is one kind of direct interaction, when the presenter do not feel familiar with face to face communication, he will get nervous and loose his concentration when giving the presentation. But, if we usually use direct communication every day, we will not nervous to give the presentation. I believe that we all as modern people with modern lifestyle have to try to interact with face to face communication like primitive people do, because direct communication is the best way to establish a good relationship with others.
            Talking about interaction and communication,when we start to communicate with others it means that we start to cooperate and work with others too. Then, when we cooperate we need some attitudes to support our interaction. The attitudes are respectable, responsible, and decency. If we do not have those attitudes, we cannot cooperate with other because they will think we are selfish, arrogant, and they will think twice to accept our request. We will find these attitudes when we communicate face to face with other people.
            To establish the interaction and relationship with other people we have to respect other people especially with people who older than us. Respectable means that we have to honor and estimate other people opinion. For example when we do something wrong, our parents will know about that and they will give us some advices. We have to show our respect to our parents when they give the advices and opinions, we have to listen well and try to accept their advice. But, if we do not listen and do not care about what they have said, it means we do not respect our parents consequently parents will get angry with us, because our parents angry, we will feel annoyed inside, it will cause some troubles like fight between parents and children. The same thing will happened if we also do not respect other people like friends, teacher, neighbors, and other citizens who give us advices, opinions, or just tell their experiences. If we do not listen and respond what they said, it will create a fight and opponent. At the end we just cannot cooperate with other peoples. And that’s all what primitive people do, they give their respect to other people when they talk. And respectable is a nature of direct interaction which is they done every day, and it will be the part of their culture. If we compare primitive and modern people’s respect, we have to say that we as modern people give less honor to other than primitive people. I think it happened because we rarely use direct communication. For example we use telephone to communicate with our parents, when they give us advices throught the telephone, we do not have to stay and listen for them. We can just put the telephone on the table and do other activity because our parent can not see what we do ehen they talking. So, we have to start growing our respectability to succed our interaction and cooperation with others.
            When we communicate and interact with other people, it will create mutual relationship which give us some responsbility  to take. For example we ask our friend to borrow a book, if they permit us, it means they give a responsibility to take care of the book, and we have to do that. if we do not have any responsible  attitude, we do not want to take care of the book, then it will come with problem like we lose the book, or we broke the book. If it happened, the relationship between us and our friend will be ruined. Respectable, responsible, and decency are the part of direct interaction. We should try to remain the direct communication like what primitive people do to be a person with some attitude that can bring us to be a better person with a better life. And I think we would better reducing the use of technology to fix some problems that cause by technology itself.
            At the last, we can see the differences between primitive and modern lifestyle. For some aspects in our live like healthy, communication, interaction, exercising, and cultural, I think primitive people do it better than us. Although we as modern people has put our self at the interface of globalization, it will not guarantee us to have a better live in the future, but technology and globalization make our life easier than before. I believe that nothing is perfect, primitive people may be can be better than us in cultural and interaction, but modern people also get more advantages than primitive people in education and technology. So, the best way to live this life is balancing some aspect in our life. We cannot imitate all of primitive lifestyle in this global era, but we also can not follow all of modern lifestyle. If we can balance our life, we can be a better person, we can make a better life, and then we can create a better future.

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makalah sistem koloid

SISTEM KOLOID
A.KOLOID
Sistem koloid (selanjutnya disingkat "koloid" saja) merupakan suatu bentuk campuran (sistem dispersi) dua atau lebih zat yang bersifat homogen namun memiliki ukuran partikel terdispersi yang cukup besar (1 - 100 nm), sehingga terkena efek Tyndall. Bersifat homogen berarti partikel terdispersi tidak terpengaruh oleh gaya gravitasi atau gaya lain yang dikenakan kepadanya; sehingga tidak terjadi pengendapan, misalnya. Sifat homogen ini juga dimiliki olehlarutan, namun tidak dimiliki oleh campuran biasa (suspensi).
Keadaan koloid bukan ciri dari zat tertentu karena semua zat, baik padat, cair, maupun gas, dapat dibuat dalam keadaan koloid.Sistem koloid sangat berkaitan erat dengan hidup dan kehidupan kita sehari-hari. Cairan tubuh, seperti darah adalah sistem koloid, bahan makanan seperti susu, keju, nasi, dan roti adalah sistem koloid. Cat, berbagai jenis obat, bahan kosmetik, tanah pertanian juga merupakan sistem koloid.Karena sistem koloid sangat berpengaruh bagi kehidupan sehari-hari, kita harus mempelajarinya lebih mendalam agar kita dapat menggunakannya dengan benar dan dapat bermanfaat untuk diri kita.
Koloid adalah suatu campuran “metastabil” (seolah olah stabil, tapi akan memisah setelah waktu tertentu). Koloid berbeda dengan larutan.
Di dalam larutan koloid secara umum, ada 2 zat sebagai berikut :
- Zat terdispersi, yakni zat yang terlarut di dalam larutan koloid
- Zat pendispersi, yakni zat pelarut di dalam larutan koloid
Berdasarkan fase terdispersi maupun fase pendispersi suatu koloid dibagi sebagai berikut :
Fase Terdispersi
Pendispersi
Nama koloid
Contoh
Gas
Gas
Bukan koloid, karena gas bercampur secara homogen
Gas
Cair
Busa
Buih, sabun, ombak, krim kocok
Gas
Padat
Busa padat
Batu apung, kasur busa
Cair
Gas
Aerosol cair
Obat semprot, kabut, hair spray di udara
Cair
Cair
Emulsi
Air santan, air susu, mayones
Cair
Padat
Gel
Mentega, agar-agar
Padat
Gas
Aerosol padat
Debu, gas knalpot, asap
Padat
Cair
Sol
Cat, tinta
Padat
Padat
Sol Padat
Tanah, kaca, lumpur
B. SIFAT KOLOID
a. Efek Tyndall
Efek Tyndall ialah gejala penghamburan berkas sinar (cahaya) oleh partikel-partikel koloid. Hal ini disebabkan karena ukuran molekul koloid yang cukup besar. Efek tyndall ini ditemukan oleh John Tyndall (1820-1893), seorang ahli fisika Inggris. Oleh karena itu sifat itu disebut efek tyndall.
Efek tyndall adalah efek yang terjadi jika suatu larutan terkena sinar. Pada saat larutan sejati disinari dengan cahaya, maka larutan tersebut tidak akan menghamburkan cahaya, sedangkan pada sistem koloid, cahaya akan dihamburkan. hal itu terjadi karena partikel-partikel koloid mempunyai partikel-partikel yang relatif besar untuk dapat menghamburkan sinar tersebut. Sebaliknya, pada larutan sejati, partikel-partikelnya relatif kecil sehingga hamburan yang terjadi hanya sedikit dan sangat sulit diamati.
Contoh: sinar matahari yang dihamburkan partikel koloid di angkasa, hingga langit berwarna biru pada siang hari dan jingga pada sore hari ; debu dalam ruangan akan terlihat jika ada sinar masuk melalui celah.
b. Gerak Brown
Gerak Brown ialah gerakan partikel-partikel koloid yang senantiasa bergerak lurus tapi tidak menentu (gerak acak/tidak beraturan). Jika kita amati koloid dibawah mikroskop ultra, maka kita akan melihat bahwa partikel-partikel tersebut akan bergerak membentuk zigzag. Pergerakan zigzag ini dinamakan gerak Brown. Partikel-partikel suatu zat senantiasa bergerak. Gerakan tersebut dapat bersifat acak seperti pada zat cair dan gas( dinamakan gerak brown), sedangkan pada zat padat hanya beroszillasi di tempat ( tidak termasuk gerak brown ). Untuk koloid dengan medium pendispersi zat cair atau gas, pergerakan partikel-partikel akan menghasilkan tumbukan dengan partikel-partikel koloid itu sendiri. Tumbukan tersebut berlangsung dari segala arah. Oleh karena ukuran partikel cukup kecil, maka tumbukan yang terjadi cenderung tidak seimbang. Sehingga terdapat suatu resultan tumbukan yang menyebabkan perubahan arah gerak partikel sehingga terjadi gerak zigzag atau gerak Brown.
Semakin kecil ukuran partikel koloid, semakin cepat gerak Brown yang terjadi. Demikian pula, semakin besar ukuran partikel koloid, semakin lambat gerak Brown yang terjadi. Hal ini menjelaskan mengapa gerak Brown sulit diamati dalam larutan dan tidak ditemukan dalam campuran heterogen zat cair dengan zat padat (suspensi). Gerak Brown juga dipengaruhi oleh suhu. Semakin tinggi suhu sistem koloid, maka semakin besar energi kinetik yang dimiliki partikel-partikel medium pendispersinya. Akibatnya, gerak Brown dari partikel-partikel fase terdispersinya semakin cepat. Demikian pula sebaliknya, semakin rendah suhu sistem koloid, maka gerak Brown semakin lambat.

c. Adsorbsi Koloid
Adsorpsi ialah peristiwa penyerapan partikel atau ion atau senyawa lain pada permukaan partikel koloid yang disebabkan oleh luasnya permukaan partikel. (Catatan : Adsorpsi harus dibedakan dengan absorpsi yang artinya penyerapan yang terjadi di dalam suatu partikel).
.Contoh: koloid antara obat diare dan cairan dalam usus yang akan menyerap kuman penyebab diare.
Koloid Fe(OH)3 akan mengadsorbsi ion H+ sehingga menjadi bermuatan +. Adanya muatan senama maka koloid Fe(OH), akan tolak-menolak sesamanya sehingga partikel-partikel koloid tidak akan saling menggerombol.
Koloid As2S3 akan mengadsorbsi ion OH- dalam larutan sehingga akan bermuatan - dan tolak-menolak dengan sesamanya, maka koloid As2S3 tidak akan menggerombol.
d. Muatan Koloid dan Elektroforesis
Muatan Koloid ditentukan oleh muatan ion yang terserap permukaan koloid. Elektroforesis adalah gerakan partikel koloid karena pengaruh medan listrik.
Karena partikel koloid mempunyai muatan maka dapat bergerak dalam medan listrik. Jika ke dalam koloid dimasukkan arus searah melalui elektroda, maka koloid bermuatan positif akan bergerak menuju elektroda negatif dan sesampai di elektroda negatif akan terjadi penetralan muatan dan koloid akan menggumpal (koagulasi).
Contoh: cerobong pabrik yang dipasangi lempeng logam yang bermuatan listrik dengan tujuan untuk menggumpalkan debunya.
e. Koagulasi Koloid
Koagulasi koloid adalah penggumpalan koloid karena elektrolit yang muatannya berlawanan.
Contoh: kotoran pada air yang digumpalkan oleh tawas sehingga air menjadi jernih.
Faktor-faktor yang menyebabkan koagulasi:
·         Perubahan suhu.
·          Pengadukan.
·         Penambahan ion dengan muatan besar (contoh: tawas).
·         Pencampuran koloid positif dan koloid negatif.
Koloid akan mengalami koagulasi dengan cara:
1.      Mekanik
Cara mekanik dilakukan dengan pemanasan, pendinginan atau pengadukan cepat


2.      Kimia
Dengan penambahan elektrolit (asam, basa, atau garam).
Contoh:      susu + sirup masam —> menggumpal
Lumpur + tawas —> menggumpal
Dengan mencampurkan 2 macam koloid dengan muatan yang berlawanan.
Contoh:     Fe(OH)3 yang bermuatan positif akan menggumpal jika dicampur As2S3 yang bermuatan negatif.
f. Koloid Liofil dan Koloid Liofob
- Koloid Liofil : koloid yang mengadsorbsi cairan, sehingga terbentuk selubung di sekeliling koloid.
Contoh: agar-agar.
- Koloid Liofob : kolid yang tidak mengadsorbsi cairan. Agar muatan koloid stabil, cairan pendispersi harus bebas dari elektrolit dengan cara dialisis, yakni pemurnian medium pendispersi dari elektrolit.
g. Emulasi
Emulasi adalah kolid cairan dalam medium cair. Agar larutan kolid stabil, ke dalam koloid biasanya ditambahkan emulsifier, yaitu zat penyetabil agar koloid stabil.
Contoh: susu merupakan emulsi lemak di dalam air dengan kasein sebagai emulsifier.
h. Kestabilan Koloid
·         Banyak koloid yang harus dipertahankan dalam bentuk koloid untuk penggunaannya.
Contoh: es krim, tinta, cat.
Untuk itu digunakan koloid lain yang dapat membentuk lapisan di sekeliling koloid tersebut. Koloid lain ini disebut koloid pelindung.
Contoh: gelatin pada sol Fe(OH)3.
·         Untuk koloid yang berupa emulsi dapat digunakan emulgator yaitu zat yang dapat tertarik pada kedua cairan yang membentuk emulsi
Contoh: sabun deterjen sebagai emulgator dari emulsi minyak dan air.
i. Pemurnian Koloid
Untuk memurnikan koloid yaitu menghilangkan ion-ion yang mengganggu kestabilan koloid, dapat dilakukan cara dialisis. Koloid yang akan dimurnikan dimasukkan ke kantong yang terbuat dari selaput semipermeabel yaitu selaput yang hanya dapat dilewati partikel ion saja dan tidak dapat dilewati molekul koloid.
Contoh: kertas perkamen, selopan atau kolodion.
Kantong koloid dimasukkan ke dalam bejana yang berisi air mengalir, maka ion-ion dalam koloid akan keluar dari kantong dan keluar dari bejana dan koloid tertinggal dalam kantong. Proses dialisis akan di percepat jika di dalam bejana diberikan arus listrik yang disebut elektro dialisis.
Proses pemisahan kotoran hasil metabolisme dari darah oleh ginjal termasuk proses dialisis. Maka apabila seseorang menderita gagal ginjal, orang tersebut harus menjalani “cuci darah” dengan mesin dialisator di rumah sakit. Koloid juga dapat dimurnikan dengan penyaring ultra.
C. PEMBUATAN SISTEM KOLOID
  1. Cara Kondensasi
Pembuatan sistem koloid dengan cara kondensasi dilakukan dengan cara penggumpalan partikel yang sangat kecil. Penggumpalan partikel ini dapat dilakukan dengan cara sebagai berikut:
·         Reaksi Pengendapan
Pembuatan sistem koloid dengan cara ini dilakukan dengan mencampurkan larutan elektrolit sehingga menghasilkan endapan.
Contoh: AgNO3 + NaCl —> AgCl(s) + NaNO3
·         Reaksi Hidrolisis
Reaksi hidrolisis adalah reaksi suatu zat dengan air. Sistem koloid dapat dibuat dengan mereaksikan suatu zat dengan air.
Contoh: AlCl3 +H2O —> Al(OH)3(s) + HCl
·         Reaksi Redoks
Pembuatan koloid dapat terbentuk dari hasil reaksi redoks. Contoh: pada larutan emas
Reaksi: AuCl3 + HCOH —> Au + HCl + HCOOH
·         Reaksi Pergeseran
Contoh: pembuatan sol As2S3 dengan cara mengalirkan gas H2S ke dalam laruatn H3AsO3 encer pada suhu tertentu.
Reaksi: 2 H3AsO3 + 3 H2S —> 6 H2O + As2S3
·         Reaksi Pergantian Pelarut
Contoh: pembuatan gel kalsium asetat dengan cara menambahkan alkohol 96% ke dalam larutan kalsium asetat jenuh.
2.Cara Dispersi
Pembuatan sistem koloid dengan cara dispersi dilakukan dengan memperkecil partikel suspensi yang terlalu besar menjadi partikel koloid, pemecahan partikel-partikel kasar menjadi koloid.
·         Cara Mekanik
Ukuran partikel suspensi diperkecil dengan cara penggilingan zat padat, dengan menghaluskan butiran besar kemudian diaduk dalam medium pendispersi.
Contoh: Gumpalan tawas digiling, dicampurkan ke dalam air akan membentuk koloid dengan kotoran air.
Membuat tinta dengan menghaluskan karbon pada penggiling koloid kemudian didispersikan dalam air.
Membuat sol belerang dengan menghaluskan belerang bersama gula (1:1) pada penggiling koloid, kemudian dilarutkan dalam air, gula akan larut dan belerang menjadi sol.
·         Cara Peptisasi
Pembuatan koloid dengan cara peptisasi adalah pembuatan koloid dengan menambahkan ion sejenis, sehingga partikel endapan akan dipecah.
Contoh:     sol Fe(OH)3 dengan menambahkan FeCl3.
sol NiS dengan menambahkan H2S.
karet dipeptisasi oleh bensin.
agar-agar dipeptisasi oleh air.
endapan Al(OH)3 dipeptisasi oleh AlCl3.
·         Cara Busur Bredia/Bredig
Pembuatan koloid dengan cara busur Bredia/Bredig dilakukan dengan mencelupkan 2 kawat logam (elektroda) yang dialiri listrik ke dalam air, sehingga kawat logam akan membentuk partikel koloid berupa debu di dalam air.
·         Cara Ultrasonik
yaitu penghancuran butiran besar dengan ultrasonik (frekuensi > 20.000 Hz)
campuran homogen.
Campuran homogen disebut larutan, contoh: larutan gula dalam air. Campuran heterogen dapat dibedakan menjadi 2 macam, yaitu: Sistem koloid termasuk dalam bentuk campuran. Campuran terbagi menjadi 2, yaitu:

1. Suspensi, contoh: pasir dalam air.
2. Koloid, contoh: susu dengan air.

D. KOMPONEN PENYUSUN KOLOID
Yaitu:
1. Fase kontinyu : medium pendispersi jumlahnya lebih banyak.
2. Fase diskontinyu : medium terdispersi jumlahnya labih banyak.

E. BENTUK PARTIKEL KOLOID
1. Bulatan : misalnya virus, silika.
2. Batang : misalnya virus.
3. Piringan : misalnya globulin dalam darah.
4. Serat : misalnya selulosa.

F. PENGGUNAAN SISTEM KOLOID
1. Obat-obatan : salep, krim, minyak ikan.
2. Makanan : es krim, jelly dan agar-agar.
3. Kosmetik : hair cream, skin spray, body lotion.
4. Industri : tinta, cat.

G.BEBERAPA MACAM KOLOID
1.      Aerosol
adalah sistem koloid di mana partikel padat atau cair terdispersi dalam gas.
Contoh: aerosol padat: debu, asap.
aerosol cair: kabut, awan.
Bahan pendingin dan pendorong yang sering digunakan adalah Kloro Fluoro Karbon (CFC).
2.      Emulsi
adalah sistem koloid di mana zat terdispersi dan pendispersi adalah zat cair yang tidak dapat bercampur. Misalnya: Emulsi minyak dalam air: santan, susu, lateks, minyak ikan. Emulsi air dalam minyak: mentega, minyak rambut, minyak bumi.
Untuk membentuk emulsi digunakan zat pengemulsi atau emulgator yaitu zat yang dapat tertarik oleh kedua zat cair tersebut.
Contoh: sabun untuk mengemulsikan minyak dan air.
kasein sebagai emulgator pada susu.
3.      Sol
adalah suatu sistem koloid di mana partikel padat terdispersi dalam zat cair.

No.
Hidrofob
Hidrofil
a.
Tidak menarik molekul air tetapi mengadsorbsi ion
Menarik molekul air hingga menyelubungi partikel terdispersi
b.
Tidak reversible, apabila mengalami koagulasi sukar menjadi sol lagi
Reversibel, bila mengalami koagulasi akan dapat membentuk sol lagi jika ditambah lagi medium pendispersinya
c.
Biasanya terdiri atas zat anorganik
Biasanya terdiri atas zat organik
d.
Kekentalannya rendah
Kekentalannya tinggi
e.
Gerak Brown terlihat jelas
Gerak Brown tidak jelas
f.
Mudah dikoagulasikan oleh elektrolit
Sukar dikoagulasikan oleh elektrolit
g.
Umumnya dibuat dengan cara kondensasi
Umumnya dibuat dengan cara dispersi
h.
Efek Tyndall jelas
Efek Tyndall kurang jelas
i.
Contoh: sol logam, sol belerang, sol Fe(OH)3, sol As2S3, sol sulfida
Contoh: sol kanji, sol protein, sol sabun, sol gelatin

4.      Gel/Jel
adalah koloid liofil setengah kaku.
Contoh: agar-agar, lem kanji, selai, jelly untuk menata rambut.
5.      Buih
adalah sistem koloid dari gas yang terdispersi dalam zat cair.
Contoh: sabun, detergen, protein.
Zat-zat yang dapat memecah/mencegah buih yaitu eter, isoamil alkohol.

H. KOLOID DALAM KEHIDUPAN

Sifat karakteristik kolid yang penting, yaitu sangat bermanfaat untuk mencampur zat-zat yang tidak dapat saling melarutkan secara homogen dan bersifat stabil untuk produksi skala besar. Oleh karena sifat tersebut, sistem koloid menjadi banyak kita jumpai dalam industri (aplikasi kolid untuk produksi cukup luas). Tetapi selain industri, sistem koloid juga banyak dapat kita jumpai dsalam kehidupan kita sehari-hari, contohnya saja di alam, kedokteran, pertanian, dsb;

- Penggumpalan darah
Darah mengandung sejumlah kolid protein yangbermuatan negative. Jika terdapat luka kecil, maka luka tersebut dapat doibati dengan pensil stiptik atau tawas yang mengandung ion-ion Al+3 dan Fe+3, dimana ion-ion tersebut akan membantu menetralkan muatan-muatan partikel koloid protein danmembnatu penggumpalan darah.

- Pembentukan delta di muara sungai
Air sungai mengandung partikel-partikel koloid pasir dan tanah liat yang bermuatan negatif. Sedangkan air laut mengandung ion-ion Na+, Mg+2, dan Ca+2 yang bermuatan positif. Ketika air sungai bertemu di laut, maka ion-ion positif dari air laut akanmenetralkan muatan pasir dan tanah liat. Sehingga, terjadi koagulasi yang akan membentuk suatu delta.

- Pengambilan endapan pengotor
Gas atau udara yang dialirkan ke dalam suatu proses industri seringkali mangandung zat-zat pengotor berupa partikel-partikel koloid. Untukmemisahkan pengotor ini, digunakan alat pengendap elektrostatik yang pelat logamnya yang bermuatan akan digunakan untuk menarik partikel-partikel koloid.

- Pemutihan gula
Dengan melarutkan gula ke dalam air, kemudian larutan dialirkan melalui sistem koloid tanah diatomae atau karbon, partikel-partikel koloid kemudian akan mengadsorbsi zat warna tersebut. Sehingga gula tebu yang masih berwarna dapat diputihkan.




I. PENJERNIHAN AIR SUNGAI
Air dapat dijernihkan berdasarkan sifat-sifat koloid, yaitu koagulasi dan absorpsi. Seperti yang telah dijelaskan sebelumnya, proses koagulasi terjadi akibat tidak stabilnya sistem koloid; yang disebabkan penambahan zat elektrolit ke dalam sistem koloid tersebut. Sedangkan absorpsi adalah proses ketika permukaan koloid menyertakan zat lain. Air sungai atau air sumur yang keruh mungkin mengandung lumpur (sol tanah liat), zat-zat warna, detergen, pestisida, dan lain-lain.
Zat koagulasi yang ditambahkan pada proses penjernihan air adalah tawas, K 2 SO 4 A1 2 (SO 4 ) 3 . Zat A1 2 (SO 4 ) 3 dalam air akan terhidrolisis membentuk koloid A1(OH) 3 . Koloid Al(OH) 3 yang terbentuk akan mengabsorpsi, menggumpalkan, dan mengendapkan kotoran-kotoran dalam air keruh. Ion Al 3+ dari koloid Al(OH) 3 akan menggumpalkan koloid tanah liat yang bermuatan negatif. Di samping itu, koloid Al(OH) 3 akan mengabsorpsi zat-zat seperti zat-zat warna, detergen, pestisida, dan lain-lain yang terdispersi dalam air keruh tersebut.

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