Thursday, October 21, 2010

Why smoking is so harmful? 

The word "tobacco" is thought to derive from the Native American word "tabago," for a Y-shaped pipe used in sniffing tobacco powder. Cigarettes and other forms of tobacco consist of dried tobacco leaves, and other ingredients added for flavor and other properties.

Some facts related with smoking:
- Smoking is the second major cause of death in the world. It's responsible for the death of one in ten adults worldwide.
- Smoking accounts for about 80-90% of all chronic obstructive pulmonary disease.
- Smoking is involved in 85% of all lung cancer deaths.
- Smoking is the major cause of cancer of the lips, tongue, mouth, pharynx, larynx and esophagus.
- Smoking has many other harmful effects in the body, a too long list to include it here.

Why smoking causes cancer? It's because tobacco and tobacco smoke contain more than 60 carcinogenic compounds. In general, more than 4,000 individual substances have been identified in tobacco smoke, including carbon monoxide, hydrogen cyanide, ammonia and other toxic irritants.

Besides all the harmful effects of tobacco, it's addictive, and this explains why although 70% of smokers want to quit and 35% attempt to quit each year, fewer than 7% succeed. The main reason why tobacco becomes addictive is due to its content of nicotine, which alters brain functioning.

Nicotine is a naturally occurring liquid alkaloid. An alkaloid is an organic compound made out of carbon, hydrogen, nitrogen and sometimes oxygen. These chemicals have potent effects on the human body. For example, many people enjoy the stimulating effects of another alkaloid, caffeine.

When you smoke, nicotine is absorbed through the skin and mucosal lining of the mouth and nose or by inhalation in the lungs. Once in the body, it activates the same reward system as do other drugs such as cocaine or amphetamine, although to a lesser degree. In the brain, nicotine increases the level of the neurotransmitter dopamine, which is a chemical in the brain responsible for feelings of pleasure. The acute effects of nicotine subside within minutes, so people continue dosing themselves frequently throughout the day to maintain the pleasurable effects of nicotine and to prevent withdrawal symptoms.

Voltaic Cell Simulation

Why the sky is blue? 

We all can look up to the sky and see its beautiful blue colour. Why is it blue, and not red, or white for instance?

As I commented in the "Vegetables post", an object is coloured because of the light that it reflects. The white light from the sun contains all the wavelengths, but when it impacts on an object some of its wavelengths are absorbed and some reflected. For example blue objects reflect 'blue' light, which is light with a pretty short wavelength.

There is a phenomena named Rayleigh scattering, that consists on the scattering of light by particles much smaller than its wavelength. This effect is especially strong when light passes through gases.

Each of the wavelengths of light suffers a different scattering when it encounters the gas particles that form the atmosphere (nitrogen, oxygen...). This effect is more prominent in the case of short light wavelengths, that are the blue end of the visible spectrum, so the blue light becomes much more dispersed and it can be seen from every direction, as you can see in the drawing below. This gives us the impression that the sky is blue. On the other hand, the red colour is scattered much less, so it can be only seen from certain directions. In the drawing below, both Observer 1 and Observer 2 can see the blue light, but only Observer 2 is in the right direction to see the red one, and that's why we see those beautiful red skies at sunset sometimes.

Then, why the clouds are white? Well, the water droplets that form the clouds have a much larger size than the gas particles of the air, and they scatter all the wavelenghts of light in the same extent, so all of them are reflected equally and we receive then the full colour of light, that is white.

Chemistry joke of the week 

A neutron walks into a bar, sits down and asks for a drink. Finishing, the neutron asks "How much?"
The bartender says, "For you, no charge."

[Explanation for non-chemists: a neutron is a particle that has no charge. Proton are those with positive charge, and electrons those with negative charge.]

Why do onions make you cry? 

Who has never cried while cutting an onion? (well, apart from those who have never cut one hehehe). This is a little explanation in easy terms.

Inside the onion cells there are some chemical compounds that contain sulfur. When you cut an onion its cells are broken and those chemical compounds then undergo a reaction that transforms them into a more volatile sulfured products, which are released into the air.

These sulfured compounds react with the moisture in your eyes forming sulfuric acid, which produces a burning sensation. The nerve endings in your eyes are very sensitive and so they pick up on this irritation. The brain reacts by telling your tear ducts to produce more water, to dilute the irritating acid. So you cry to keep your eyes protected from the acid.

There are some tricks to make onion-dicing less problematic:
- Chop the onion under cold water. The volatile sulfured compounds will be released but then they react with the water, instead of reaching your eyes.
- You can freeze the onion for 10 minutes before cutting it. The cold temperature of the onion will slow down the chemical reaction which forms the volatile sulfured compunds.

Wednesday, October 20, 2010

Mungkin pada sepasang matanya yang hening yang selalu menjeling tajam atau yang kadang kala malu-malu memberikan kerlingan manja.
Boleh jadi pada bibirnya yang tak jemu-jemu menyerlahkan senyuman manis, atau yang sekali-sekala memberikan kucupan mesra di dahi umi juga, ayah, suami dan pipi munggil anak-anak.
Atau mungkin juga pada hilai tawanya yang gemersik dan suara manjanya yang boleh melembut sekaligus melembutkan perasaan.
Sejuta perkataan belum cukup untuk menceritakan kecantikan perempuan. Sejuta malah berjuta-juta kali ganda perkataan pun masih belum cukup untuk mendefinisikan tentang keindahan perempuan. 
Kitalah perempuan itu. Panjatkan kesyukuran kehadrat Tuhan kerana menjadikan kita perempuan dan memberikan keindahan-keindahan itu.
Namun, betapa pun dijaga, dipelihara, dibelai dan ditatap di hadapan cermin saban waktu, tiba masanya segalanya akan pergi jua. Wajah akan suram, mata akan kelam.
Satu sahaja yang tidak akan dimamah usia, sifat keperempuanan yang dipupuk dengan iman dan ibadah.
Anda ingin lebih cantik dan menarik?
# Jadikanlah Ghadhdul Bashar (menundukkan pandangan) sebagai "hiasan mata" anda, nescaya akan semakin bening dan jernih.
# Oleskan "lipstik kejujuran" pada bibir anda, nescaya akan semakin manis.
# Gunakanlah "pemerah pipi" anda dengan kosmetik yang terbuat dari rasa malu yang dibuat dari salon Iman.
# Pakailah "sabun istighfar" yang menghilangkan semua dosa dan kesalahan yang anda lakukan.
# Rawatlah rambut anda dengan "selendang islami" yang akan menghilangkan kelemumur pandangan lelaki.
# Hiasilah kedua tangan anda dengan gelang tawadhu' dan jari-jari anda dengan cincin ukhuwwah.
# Sebaik-baiknya kalung anda adalah kalung "kesucian."
# Bedaklah wajah anda dengan "air wudhu."

Name: Millatina Bt Mohd Ghazally
Birthday: 23 May 1990
Email Address: vanskomplotan@yahoo.com
Address: PT841 Taman Desa An-Nur Kg Panji 16100 Kota Bharu Kelantan
Education: Universiti Pendidikan Sultan Idris ( Chemistry In Education)
My Philosophy: Mind Ur Own Bussiness