Water has a great solvent power. This is due to the polarity and exceptional H- bonding ability. It can dissolve ionic compounds through ion-dipole forces that separate the ions from the solid and keep them in solution. Water is a non-ionic, polar molecule that can dissolve most compounds that are non-ionic and polar, like itself and most ionic compounds as well.

Non-ionic refers to the compound with no charge while polar means that there is a charge difference within the molecule. The oxygen in water is negatively charged while the two hydrogen atoms are positively charged. Both charges are very weak and this gives the molecule an overall neutral charge. Normally acid or base solutions can dissolve other solutions or compounds of a like pH, but water, being neutral, is attracted to, and therefore dissolves solutions or compounds of any pH. Thus, water can dissolve more substances than any other liquid.

As water can dissolve many substances, water is the environmental and biological solvent that forms complex solutions known as lakes, oceans, rivers and cellular fluids. Aquatic animals and plants would not be able to survive without dissolved oxygen and carbon dioxide. Daily human activity such as eating, drinking, inhaling or opening doors allow toxins to be absorbed by the body. The kidney plays a role in filtering the poisons back out. Water plays an important part in this process. Water, a great solvent, washes through the kidney and removes the toxins that were collected from the tissues. Without a solvent, the kidney would not be able to extract the toxins collected and cause harm to itself. Hence, water is called the “universal solvent” because it dissolves more substances than any other liquid. This means that wherever water goes, either through the ground or through our bodies, it takes along valuable chemicals, minerals and nutrients.

In this modern day, there is a constant conflict between the industrial society and the environment. Acid rain is the result of human activities that causes the build up of acid that occurs as wet deposition in rain, snow or fog and as dry deposition on solid particles. One of the main forms of acid deposition is through the transformation of sulphur dioxide and nitrogen oxides into dry or moist secondary pollutants such as sulphuric acid (H₂SO₄), ammonium nitrate (NH₄NO₃) and nitric acid (HNO₃). The oxidation of SO₂ forms sulphur trioxide that will form sulphuric acid (H₂SO₄) on contact with water, including any in the atmosphere.  The reaction of N₂ and O₂ will form nitrogen oxides. NO is formed during combustions, especially in car engines and electric power plants. It forms NO₂ and HNO₃ in the air in the process that creates smog. At night, NO_x is then converted to N₂O₅, which hydrolyzes to HNO₃ in the presence of water. The strong acids such as H₂SO₄ and HNO₃ are a main concern as it dramatically affects the ph of rain.

These acidic particle and vapours occur as the pollutants are transported in the atmosphere over a wide distance. Acidic particles and vapours are deposited via two processes which are wet and dry deposition. Wet deposition is acid rain, the process by which acids with a pH normally below 5.6 are removed from the atmosphere in rain, snow, sleet or hail. Dry deposition takes place when particles such as fly ash, sulphates, nitrates, and gases, are deposited on, or absorbed onto, surfaces. The gases can then be converted into acids when they contact water.

Acid rain affects the environment in many ways. Certain shellfish and fishes die at pH values between 4.5 and 5.0 and at pH 5, most fish eggs cannot hatch. This loss of fish is a major concern that has been around for awhile. Forests have also been affected as the acid rain removes nutrients and releases toxic substances from the soil. Even if the soil is buffered, acidic fog and clouds can remove essential nutrients from the surface of leafs.  Aluminosilicates that make up most soils are extremely insoluble in water. The Al³⁺ ion is bonded to OH^- and O^2- ions in complex structures. The continual contact with the H₃O⁺ in acid rain causes these ions to react with bound Al³⁺ and dissolve. This ion is toxic to fish and will also carry away ions that serve as nutrients for plants and animals. Besides that, acid rain also dissolves calcium carbonate in marble and limestone of buildings and monuments. However, these same properties are responsible for saving lakes bounded by limestone-rich soil. It keeps the lake at a relatively stable pH, where it remains mildly basic.

Joseph Nicephroe took the first permanent photograph. The first image was captured on a pewter plate covered with bitumen of Judea derived from petroleum. In 1840, Fox Talbot introduced silver chloride and negative images that were used as the precursor to today’s film camera. George Eastman introduced a gel and paper based film that does away with the need for plates and chemical bottles.

The film is coated in special chemicals known as photographic detectors. This chemicals, change when is in contact with light energy. The main photographic chemical used today is silver halide that destabilizes in accordance to the wavelength of the light and forms a latent image of what is being photographed.

Photographic paper is coated with silver halide grains on the image producing side.  For colour prints, the grains are sensitized to blue, green and red lights. Colour film requires the use of reducing chemicals that expose grains of silver halide to create pure silver. The oxidized developers react with the image-forming layers of the film to create colour. This process has to be taken in a dark environment as exposure of film to light will ruin the image.

Black and white photographic chemistry works in a similar manner but in their case,   the silver halide grains are not sensitized to specific colours. The images are captured and the prints are developed in a similar fashion. As there are no colour adjustments needed in black and white photography, many photographers choose to develop these prints in their own dark rooms. Producing your own prints allows you to have more control over the length of time that the paper is exposed to the light. The difference in the exposure time can increase or decrease the amount of contrast in the resulting image.

Do you ever wonder why it happens? Has it ever happen to you at all? Personally, i don’t cook all that much and even if i do, its the instant kind. But i do go all out sometimes.

I remember crying my eyes out once while cutting onions and wondering why i was tearing up. Everyone knows you can get a little teary when cutting onions, but do we really know what causes it? Well, the secret is in the cells of the onions.

When you cut an onion, you release the content of the cells causing them to react with each other. The contents in mind are amino acids and sulfenic acids. When these compound react, they form propanethiol S-oxide. This volatile compound is what cause your eyes to tear up. The gas reacts with the water in your tears to form sulfuric acid, which cause a burning sensation, causing your eyes to release more tears to wash the irratating compound.

So, how do we cut onions without crying? Well, i did some research and found a few interesting answers

1) Cut onions under water (it might work for some people, but i find it hard to slice onions under water)

2) Wear goggles while cutting onions (yes, it’s true but its not a science experiment, just plain old cooking)

3) Use a fan to blow away the gases

4) Refrigerate onions before cutting them

While option 3 and 4 are helpful, but it all depends on you and which option you prefer. But you are always allowed  to do it the old fashion way and have a good cry.

I recently read an article that was about using chemotherapy to fight the aging process. Well, some might have their ears perked up at this statement but i am still a little skeptical.

A test done at the University of Michigan in Ann Arbor showed that the test subjects (20 people aged 56 to 85 years old) using Fluorouracil, a chemotherapy agent formulated as a topical cream, had their skin texture and appearance improve. However, they had to go through a stage of uncomfortableness, itch and redness.

A biochemical analysis of the test subjects’ skin showed that the skin cells were undergoing an epidermal renewal. The starters for new layers of skin, Type I and Type III pro-collagen increased. Half-way through the term of the test, the fine wrinkles  on the face appeared to relax. By the end of the test, the subjects’ skin appeared to be significantly softer.

The drug Flurouracil has actually been in use since the mid-1960s to  treat sun damaged skin that are considered the earliest stage in the development of skin cancer. It was noticed that the patients’ skin texture resembled the skin of someone younger after the initial stage of breakout of red patchy skin.

So before you go try this out, make sure you read up on the treatment and what other side-effects it causes. Then you can decide how worth it the treatment is and if you are desperate enough to go through it.