Monday, August 21, 2006

How to Clean Laboratory Glassware

My Prof. said that If I can't clean Laboratory glasswares well, I won't become a good chemist. I think it's true.

By Anne Marie Helmenstine, Ph.D.,
Cleaning laboratory glassware isn't as simple as washing the dishes. Here's how to wash your glassware so that you won't ruin your chemical solution or laboratory experiment.

Cleaning Basics

It's generally easier to clean glassware if you do it right away. When detergent is used, it's usually one designed for lab glassware, such as Liquinox or Alconox. These detergents are preferable to any dishwashing detergent you might use on dishes at home.

Much of the time, detergent and tap water are neither required nor desirable. You can rinse the glassware with the proper solvent, then finish up with a couple of rinses with distilled water, followed by final rinses with deionized water.

How to Wash Out Common Lab Chemicals

* Water Soluble Solutions
(e.g., sodium chloride or sucrose solutions) Rinse 3-4 times with deionized water then put the glassware away.

* Water Insoluble Solutions
(e.g., solutions in hexane or chloroform) Rinse 2-3 times with ethanol or acetone, rinse 3-4 times with deionized water, then put the glassware away. In some situations other solvents need to be used for the initial rinse.

* Strong Acids
(e.g., concentrated HCl or H2SO4) Under the fume hood, carefully rinse the glassware with copious volumes of tap water. Rinse 3-4 times with deionized water, then put the glassware away.

* Strong Bases
(e.g., 6M NaOH or concentrated NH4OH) Under the fume hood, carefully rinse the glassware with copious volumes of tap water. Rinse 3-4 times with deionized water, then put the glassware away.

* Weak Acids
(e.g., acetic acid solutions or dilutions of strong acids such as 0.1M or 1M HCl or H2SO4) Rinse 3-4 times with deionized water before putting the glassware away.

* Weak Bases
(e.g., 0.1M and 1M NaOH and NH4OH) Rinse thoroughly with tap water to remove the base, then rinse 3-4 times with deionized water before putting the glassware away.

Washing Special Glassware

* Glassware Used for Organic Chemistry
Rinse the glassware with the appropriate solvent. Use deionized water for water-soluble contents. Use ethanol for ethanol-soluble contents, followed by rinses in deionized water. Rinse with other solvents as needed, followed by ethanol and finally deionized water. If the glassware requires scrubbing, scrub with a brush using hot soapy water, rinse thoroughly with tap water, followed by rinses with deionized water.

* Burets
Wash with hot soapy water, rinse thoroughly with tap water, then rinse 3-4 times with deionized water. Be sure the final rinses sheet off of the glass. Burets need to be thoroughly clean to be used for quantitative labwork.

* Pipets and Volumetric Flasks
In some cases, you may need to soak the glassware overnight in soapy water. Clean pipets and volumetric flasks using warm soapy water. The glassware may require scrubbing with a brush. Rinse with tap water followed by 3-4 rinses with deionized water.

Drying or Not Drying Glassware

* Not Drying
It is inadvisable to dry glassware with a paper towel or forced air since this can introduce fibers or impurities that can contaminate the solution. Normally you can allow glassware to air dry on the shelf. Otherwise, if you are adding water to the glassware, it is fine to leave it wet (unless it will affect the concentration of the final solution). If the solvent will be ether, you can rinse the glassware with ethanol or acetone to remove the water, then rinse with the final solution to remove the alcohol or acetone.

* Rinsing with Reagent
If water will affect the concentration of the final solution, triple rinse the glassware with the solution.

* Drying Glassware
If glassware is to be used immediately after washing and must be dry, rinse it 2-3 times with acetone. This will remove any water and will evaporate quickly. While it's not a great idea to blow air into glassware to dry it, sometimes you can apply a vacuum to evaporate the solvent.

Additional Notes

* Remove stoppers and stopcocks when they are not in use. Otherwise they may 'freeze' in place.
* You can degrease ground glass joints by wiping them with a lint-free towel soaked with ether or acetone. Wear gloves and avoid breathing the fumes.
* The deionized water rinse should form a smooth sheet when poured through clean glassware. If this sheeting action is not seen, more aggressive cleaning methods may be needed.

Relationship Between Science (Chemistry) and Technology

Relationship Between Science (Chemistry) and Technology
by: salman

Technology is the application of science that is concerned with practical uses in industry. Therefore, science (chemistry) and technology need each other, because "science (chemistry) without a technology like a fruitless tree, while the technology without science is like a tree without roots" (science (chemistry) is fruitless without technology, without science technology (chemistry) is Rootless). With support resources manusis quality and natural resources sufficient and adequate, there was rapid progress in science and technology, whose products will equip people with various (1) The material is good (such as construction of buildings, various types of foods and beverages, various types of information or communication and transportation, the various devices that can generate great energy and improve the working efficiency of the machines, thus speeding / improving production, various types of medicines, clothing, soap and detergents, cosmetics, plastics, polymers, fibers, dyes, and various other items), and (2) Services / Services 9meliputi waiter: transport, telkomunikasi, hotel / lodging, security and safety for individuals or communities), so terwujudlah welfare. From the above brief description terliat that chemistry is very important to be learned and in apliksikan in life.

Friday, August 18, 2006

ChemLab v 2.0

Model ChemLab originated from academic work in computer simulation and software design at McMaster University. It has continued to be developed with extensive input from educators interested in the possible application of computer simulations for classroom and distance learning.

Model ChemLab is a unique product incorporating both an interactive simulation and a lab notebook workspace with separate areas for theory, procedures and student observations. Commonly used lab equipment and procedures are used to simulate the steps involved in performing an experiment. Users step-through the actual lab procedure while interacting with animated equipment in a way that is similar to the real lab experience.

ChemLab comes with a range of pre-designed lab experiments for general chemistry at the high school and college level. Users can expand upon the original lab set using ChemLab's LabWizard development tools, thus allowing for curriculum specific lab simulation development by educators. These user designed simulations combine both text based instructions and the simulation into a single distributable file.

Resigzed Image.

Chemistry Laboratory Safety Rules

Better Safe than Sorry
By Anne Marie Helmenstine, Ph.D.,
Some rules are NOT made to be broken. That is true of the rules used in a chemistry lab. They are really, truly for your safety and not your humiliation.

* Do Not Pipette By Mouth - Ever
You say, "But it's only water." Even if it is, how clean do you think that glassware really is? Using disposable pipettes? I know lots of people who rinse them and put them back! Learn to use the pipette bulb or automated pipetter. Don't pipette by mouth at home either. Gasoline and kerosene should be obvious, but people get hospitalized or die every year, right? I know someone who used his mouth to start the suction on a waterbed to drain it. Do you know what they put in some waterbed additives? Carbon-14. Mmmm...radiation. He couldn't retch fast enough! The lesson is that even seemingly harmless substances may be dangerous!

* Read the Chemical Safety Information
A Material Safety Data Sheet (MSDS) should be available for every chemical you use in lab. Read these and follow the recommendations for safe use and disposal of the material.

* Dress Appropriately (for chemistry lab, not fashion or the weather)
No sandals, no clothes you love more than life, no contact lenses, and long pants are preferable to shorts or short skirts. Tie long hair back. Wear safety goggles and a lab coat. Even if you aren't clumsy, someone else in the lab probably is. If you take even a few chemistry courses you will probably see people set themselves on fire, spill acid on themselves, others, or notes, splash themselves in the eye, etc. Don't be the bad example to others, remembered for all time for something stupid!

* Identify the Safety Equipment
And know how to use it! Given that some people (possibly you) will need them, know the locations of the fire blanket, extinguishers, eyewash, and shower. Ask for demonstrations! If the eyewash hasn't been used in a while the discoloration of the water is usually sufficient to inspire use of safety glasses.

* Don't Taste or Sniff Chemicals
For many chemicals, if you can smell them then you are exposing yourself to a dose that can harm you! If the safety information says that a chemical should only be used inside a fume hood, then don't use it anywhere else. This isn't cooking class - don't taste your experiments!

* Don't Casually Dispose of Chemicals Down the Drain
Some chemicals can be washed down the drain, while others require a different method of disposal. If a chemical can go in the sink, be sure to wash it away rather than risk an unexpected reaction between chemical 'leftovers' later.

* Don't Eat or Drink in Lab
It's tempting, but oh so dangerous... just don't do it!

* Don't Play Mad Scientist
Don't haphazardly mix chemicals! Pay attention to the order in which chemicals are to be added to each other and do not deviate from the instructions. Even chemicals that mix to produce seemingly safe products should be handled carefully. For example, hydrochloric acid and sodium hydroxide will give you salt water, but the reaction could break your glassware or splash the reactants onto you if you aren't careful!

* Take Data During Lab
Not after lab, on the assumption that it will be neater. Put data directly in your lab book rather than transcribing from another source (e.g., notebook or lab partner). There are lots of reasons for this, but the practical one is that it is much harder for the data to get lost in your lab book. For some experiments, it may be helpful to take data beforelab. No, I'm not telling you to dry-lab or cheat, but being able to project likely data will help you catch bad lab procedure before you are three hours or so into a project. Know what to expect. You should always read the experiment in advance.

Wednesday, August 16, 2006

Man and Love

Love is a gift of God, he is inside every human being, so he is universal. He is associated with the deepest aspects of human beings, because we sense it will never be able to understand nature in other words, love only to be felt not to think about. Also difficult to deny that love is one of the needs of human life is quite fundamental.
Love can be happy at once miserable. Kekuatanya can make people laugh, sad, whimpering or even crying. But make no mistake cry in sex was common. In love with no complaints and complaining, because no other lover goal is the goal of the lover. Moaned and groan clearly contrary to the willingness, for lovers of all deeds are always willing lover. In a hadith, the Prophet once said: "Three things come from good pembendaharaan; hide charity, hide and conceal complaints disaster."
Love is one of the most interesting themes to be discussed, written, or filmed disyairkan. Hundreds of the definition of love has been put forward by the scholars, psychologists and philosophers. Thousands of strands of beautiful poems have been woven by the poets of the world, all trying to define and a portrait of the nature of love. Tetapih love remains a mystery and the biggest puzzle for humans.
A Sufi divide love into two categories; Divine Love And Human Love. Love divine grace is essential is delegated to humans. He is the incarnation of His nature; ar-rahman ar-uterine and the impossible can be calculated with an estimated human, as it is impossible to calculate favors which has given him.
In our every breath, every cell in our blood, in each of the elements contained in soil, there is a divine love that we often do not realize. With his rahmaniyah God has revealed the beauty of the rainbow through the mediation of both our eyes, and make itself merdunya water splashing through His gift of a pair of ears. With his rahmaniyah God has given sweet taste of sugar through through our tongues. Unfortunately we often forget about giving yourself to Him. Clever-clever we are grateful, still not adequate as an expression of gratitude is too large due to the grace of God.
Second is human love. This love comes from first love. Love between men and women is a portion of divine love. Apapaun we feel about love, in the manner and extent of any small part of the love god. Tetapih sometimes lover becomes a veil between love and reality of true love. One day the veil will be lifted where purposes and a true lover will appear in all the greatness of god.
The theme of love is not be exhausted to talk. He belongs to everyone and everyone is entitled to speak about love.

1. Meaning of Love
Love is a matter of heart problems, he relates to the deepest feelings in man. It is not surprising that it has a sense of love and planting a diverse, depending on who and what is perceived by a person and how he mengeskpresikan gust love it.
In a simple love can be said as an alloy of sympathy between the two creatures. Sympathy is not only growing among men and women, will tetapih could also between man to man or woman to woman. Examples are easy to understand for this we can see in a loving relationship between a father with his son, or between a mother with her daughter.
Love is very closely adrift with human life. selintas never any people think that love is not important. They are hungry for love. Many people do not stop watching movies about love stories, both ended with a happy and vice versa. Many people like to hear dozens of songs about love that pattern. Nevertheless, almost every people never think about what and how to love it. In fact, love can be described as an art as any other art form, it requires knowledge and practice to be mengapainya.

2. Motif-motif is Driving The emergence of Love.
The motive of love is a feeling, followed by the desire and tendency to love something one's heart. He also could mean something that is inside of a person who causes he loved. Thus, it is the motive is a combination of both, the properties of a person who encourages others to love him, and feelings of love that is in the lover. Besides the existence of harmony and compatibility, as the force that will build and bind their love.
Thus, there are several motives that drive the emergence of a sense of love, that is something that is inside of her lover, especially the beauty and the beauty, the feeling of love the lover and the conformity and harmony among them. The stronger and is also perfect love caused by it. Vice versa.
When the loved one being in the top of the charm of her beauty, coupled with sempurnannya harmony and harmony that binds the two souls, will be created lasting love and eternal.
Sometimes, the lover levels of beauty it mediocre, tetapih seen so perfect in the eyes of lovers, her love will be perfect. So that beauty is relative, depending on how much love is felt by someone that, because "your love for something can make you blind and deaf."
No doubt that one lover is one of the most beautiful in the eyes of the lover of all things and beyond. It could be the perfect beauty of a woman, but can not be fully enjoyed by a man, so that his love be mediocre ..

3. Affection
According to the Indonesian general dictionary writing WJS Purwodarminto, compassion is defined by feelings of affection, feelings of love or feelings of love to someone.
In married life affection is the key to happiness. Compassion is a growth of love. When youth romance ended with marriage, then married a young family in that no longer make love-love, but it is shed each other's love to love or affection.
If one element of love lost, for example elements of responsibility, then the integrity retaklah household. Compassion is not accompanied by honesty will terancamlah happiness that household.

4. Intimacy
Intimacy comes from the intimate meaning of intimate feelings of sympathy. Intimacy is a good intimate relationship between men and women who are intoxicated by romance or already married.
Yose Ortega Y. Gasset in his novel "On Love" say "in his soul a lover feels himself united with the object of unconditional love. Unity is the fundamental unity and involve the whole existence ".
Intimacy can lead to the power of human creativity. with the intimacy of people to create various art forms in accordance with ability and talent.

5. True love
Love is based on the motives and purposes may not be lasting. So it is with love that is based on material owned by her lover, because with the loss or change something, it will disappear also love earlier. But when love is based on motifs derived from the lover's inner ssendiri and nature, her love would be eternal while there are no obstacles that cause love is lost. Barriers could include changes in circumstances (mental), the condition of the suffering lover or arising by her lover because of this suffering could weaken or even eliminate the feeling of love at all.
Therefore, the lovers are divided in two groups. The first group said that it was not true love if he could cut off by suffering or disturbance. Indications that true love is not love because of reduced levels keberpalingan lover, he also could not remove only because of the suffering endured by the lover, even he will enjoy whatever treatment her lover against him;
'My love blossomed, no matter who you are
how are you, past or present
you do not care (in my situation), so I will
you're acting like the behavior of my enemies
then I will love them
judgment against you
same as in their judgment
kuperoleh enjoyment if people insult me
I felt the reproach in the love
as a delicacy
love has been imprinted, then let them picking on me
this is called true love, which grows from a strong harmony. He hinakan himself because sanag melecehkanya lover, he loved his enemies because they like the lover who often hurt.
This is a consequence of a feeling of perfect love, despite sincere heart and soul not accept it.
The second group is different from the first, they thought it could relieve the suffering of love, because nature and human nature is naturally going to hate people who hurt him, as where he would like people who do good to him.

6. The emergence of Cause For Love
The cause of the emergence of a sense of love that there are three kinds. First sight, be it through the eye and vision care. Both assessments are good, if the outlook was not accompanied by assessments and the assumption that good, then it is unlikely that love will appear. Third, think about what he had seen and what is dancing her heart. If someone is preoccupied by matters more important (according to him) than what he had seen, then there will emerge a sense of love, although interest in it can not be eliminated. Because it is said that love is the movement of an empty soul. If the view. Assessment and thought had occurred to the heart that is empty, will emerge feeling of love.

7. Signs of Love
There are some signs that the supporters love love it:
1. Concentration in the lover's eyes
The eyes are the heart door, he pushed all the secrets contained in the liver. The eyes convey more honest than of the tongue, because the indications look more real, spontaneous, without any artificial or cultivated, while the tongue indication lafadz, who follow what the intended meaning of the speech. Eyes of someone who is in love will always be drawn to people who loved, wherever she goes.
2. Bowed shame if in view by her lover
The lovers could only close his eyes, lowered his face and looked away when looking at her lover. This is all driven by a sense of shame because of the greatness and majesty of his beloved his heart.
3. Always remember and mention the name of her lover
The name of a lover will not be forgotten at all in the heart of the lover, because his name has stuck deep inside his heart. But because keterbatasanya place in my heart, the lover can terkandang melupakannaya, because something was missing interrupt, ingatanya will return.

4. Can not wait as far away from lover
A lover would feel uneasy when he had to be away from her lover, but he will be very patient, as for the patience of a lover for far and away with her lover is apparent patience, patience is not true.

5. Anything like that favored by her lover

6. The road to the house lover was actually much closer though
7. Embarrassed when being together with her lover
8. Something fun like all the lover.
9. Jealous lover
Jealousy someone will emerge if the lover have been wronged or dihianati.
10. Like tandem
Nothing is more beautiful felt by people who are in love than be alone with a lover.
11. The existence of harmony between the two of them
harmony between the two lovers will terbina if there is a match between two of them dalamberbagai thing, many of them are sick because of her illness her lover, while he was not aware of a lover to say something, and at the same time her boyfriend also said something similar and exactly the same.

8. Meaning of Worship
Adoration is the embodiment of human love to God. because God is love only for humans, while the lovers love and the love of neighbor is a blessing that God put in the human heart.
Love that there are three kinds: love God, love for God and love with God. Loving God is the perfection of love and tuntunanya. Love for God requires that to love what is loved by Him and love anything that can help her love, menghantarkanya in proximity to His good pleasure. While love with God is the love that smell of shirk, like love people to shirk their god.

9. Mercy
Love this fellow is given the term "Twelve Pity" to distinguish between the love of god, love to parents, male-female love, love the nation and homeland.
In the letter Al-Pen paragraph 4 of the human being merciful to others, because compassion is the act of a virtuous person, while the righteous man is praised by Allah SWT.
In the essay "On Love" is the understanding that love is a feeling of unity without conditions. That means in a sense of pity belasa not contain elements of self-interest. Pity that we really shed from a sincere heart.

Source: Shaykh ibn al-Qayyim al-Jawzi, 2004. Why no love. Abla Publisher. Jakarta.

How to Write a Lab Report

Lab reports are an essential part of all laboratory courses and usually a significant part of your grade. If your instructor gives you an outline for how to write a lab report, use that. Here's a format for a lab report you can use if you aren't sure what to write or need an explanation of what to include in the different parts of the report. A lab report is how you explain what you did in experiment, what you learned, and what the results meant. Here is a standard format:

1. Title Page
Not all lab reports have title pages, but if your instructor wants one, it would be a single page that states:
* The title of the experiment.
* Your name and the names of any lab partners.
* Your instructor's name.
* The date the lab was performed or the date the report was submitted.

2. Title
The title says what you did. It should be brief (aim for ten words or less) and describe the main point of the experiment or investigation. An example of a title would be: "Effects of Ultraviolet Light on Borax Crystal Growth Rate". If you can, begin your title using a keyword rather than an article like 'The' or 'A'.

3. Introduction / Purpose
Usually the Introduction is one paragraph that explains the objectives or purpose of the lab. In one sentence, state the hypothesis. Sometimes an introduction may contain background information, briefly summarize how the experiment was performed, state the findings of the experiment, and list the conclusions of the investigation. Even if you don't write a whole introduction, you need to state the purpose of the experiment, or why you did it. This would be where you state your hypothesis.

4. Materials
List everything needed to complete your experiment.

5. Methods
Describe the steps you completed during your investigation. This is your procedure. Be sufficiently detailed that anyone could read this section and duplicate your experiment. Write it as if you were giving direction for someone else to do the lab. It may be helpful to provide a Figure to diagram your experimental setup.

6. Data
Numerical data obtained from your procedure usually is presented as a table. Data encompasses what you recorded when you conducted the experiment. It's just the facts, not any interpretation of what they mean.

7. Results
Describe in words what the data means. Sometimes the Results section is combined with the Discussion (Results & Discussion).

8. Discussion or Analysis
The Data section contains numbers. The Analysis section contains any calculations you made based on those numbers. This is where you interpret the data and determine whether or not a hypothesis was accepted. This is also where you would discuss any mistakes you might have made while conducting the investigation. You may wish to describe ways the study might have been improved.

9. Conclusions
Most of the time the conclusion is a single paragraph that sums up what happened in the experiment, whether your hypothesis was accepted or rejected, and what this means.

10. Figures & Graphs
Graphs and figures must both be labeled with a descriptive title. Label the axes on a graph, being sure to include units of measurement. The independent variable is on the X-axis. The dependent variable (the one you are measuring) is on the Y-axis. Be sure to refer to figures and graphs in the text of your report. The first figure is Figure 1, the second figure is Figure 2, etc.

11. References
If your research was based on someone else's work or if you cited facts that require documentation, then you should list these references.

( Source : )

Khalil Gibran

When love calls you, follow him, despite the steep winding road.
And when his wings merangkummu, pasrahlah and surrender,
though the sword hidden in between the wing was hurt.
And if she talks to you, believe me, even though his words interrupted dream,
like a north wind rifling through landscaping.
For as love memahkotaimu, demikuan did he crucify you.
For the sake of your growth, as well as also for the sake of pemangkasanmu.
As he was rising, kissed the tops of ketinggianmu,
tenderly caressing the softest twigs which tremble in the sunlight,
so did he menghunjam to the bottom akarmu,
ikatanmu shake of the ground.

Like a grain of wheat you reach, you get plain nude ditumbuknya,
diketamnya you, for free from your skin, rubbed, so that becomes pure white,
squeezed, squeezed into a limp material is formed,
and finally delivered to the sacred fire,
like holy bread which is dedicated to the feast of the Holy God.

Thus the character of self-love of man, so you understand the secret of the heart,
and this awareness of life make you a piece of liver.

But if the anxiety, selfhood only love and joy you seek,
it is more okay for you to cover your body, then withdrew from the board forging,
enter the world without seasons, where you can laugh, but not entirely,
where you can cry, but not after tears.

Love does not give anything, except the whole himself, fully intact.
Did not take anything, except from himself.
Love does not have or even possessed, for love is sufficient for love.

If you love, do not you say "God is in my heart,"
but should you feel, "I was in the Lord."

Love no desire other than to realize its meaning,
but if you're in love with a variety of desires,
Make it happen his way.

Melt away, flows like time,
who sings the song offerings of the night,
recognize the hurt caused by his own understanding of love,
and the blood shed by voluntary as well as joy.

Wake up at dawn at dawn with a heart as light as clouds,
grateful for a new day full of light love,
istirah in the hot afternoon peak-peak vibration contemplate love,
home in times of dusk with full gratitude in the chest cavity,
then fall asleep with a prayer for the beloved in the heart,
and a song of praise smile tugging at his lips.

Quotations about Love, from the book The Prophet, by Kahlil Gibran.

sage advice

make time to read
because it is the source of wisdom
make time to laugh
therefore his musical soul
provide time to think
because it is fundamental progress
make time for fun
because it makes young always
provide time for the faithful
because it is the mother of all peace and quiet