Tag Archives: Water

In Search of Chemist’s pure water

Chemist’s pure water which is formulated as H2O exists only in the theory. In the laboratory too, it has to be prepared from the water from the tap. The reason isits high polarity and very dielectric constant which makes it is a potent solvent. It can dissolve ionic inorganic salts, polar organic compounds, acidic, basic and polar gases. It also carries suspended matter like clay particles which are in the form of colloids. Some of these are loosely suspended and separate out with time by sedimentation and other are stable and has to be destabilized by using defloucculants to settle them out. For example, the river water continuously interacts with the rocks and soil during its flow and leaches many inorganic salts of alkali metals, alkaline earth metals in appreciable amounts and many other metal ions in trace amounts. It can absorb the lower molecular weight organic acids like formic acid and acetic acids. Gases are trapped in two ways by water. First category are gases which are acidic like carbondioxide and oxides of nitrogen, sulphur dioxide etc reacts with water and render it acidic and basic like ammonia react with it to form basic solutions. Another way by which water traps the molecules of non polar gases like oxygen, methane etc is that there are cavities in the grid of water molecules where these gases are trapped through weak Van der Wall forces.

Not only that, when water freezes, in the lattice it creates, gaseous hydrocarbons are trapped if certain conditions like availability of these gases at the time of freezing, pressure, temperature. If the conditions fall into the favorable envelope, gases are trapped. These are called gas hydrates. In fact, it has been estimated that vast amounts of methane is trapped world over in this form. Technology is being developed to tap the resource in a safe, environmental friendly and economically feasible way.

Chemist has to remove all these impurities to achieve a tentative pure water. The degree of purification depends upon the kind of experiment. For example, for the ion chromatography where presence of ions is determined at ppb or ppm level, the water used in this work has to be free from the ions under determination in a sample. This water is prepared with sophisticated water purifier called ultra purifier which removes suspended matter, kills bacteria and removes every ion present to negligible amounts. For ordinary work on a gross level determations, onetime distilled water will do the work.

This also does not last long as it is continuously absorb the gases from the environment if it is not sealed. If your laboratory is located near a highway with high volume of vehicles then due to the emission of the acidic nitrogen oxides, this water immediately turns acidic. Thus even during the conducting of experiment, special care using isolating techniques has to be taken if the correct results are to be achieved. In the analytical work, the procedures specially mention the freshly distilled water to be used.

So whenever we speak of water, it is not the pure H2O but a mixture of different salts and gases dissolved in the chemistry water. Some of these ions are required for human bodies but these should be within limits.

So the chemical composition of water is very important to know it’s potability for drinking purposes. Generally, in most of the cases treatments are necessary to make it fit for drinking.


Higgs Boson: The God Particle

How many fundamental particles make all what exists in the universe? In our days electrons, protons and neutrons were considered the fundamental particles making up the atoms. Atoms combined with each other according to some rules to make molecules which are the building blocks of the universe. As the research to probe into the heart of these fundamental particles advanced with the advent of high speed particle colliders, it has been found that itis after all not as simple as it looks. Only electron withstood the test of being the fundamental particle. It was shown that neutrons and protons are formed from other particles which have been observed in these particle smashers. We now know that protons and neutrons can be formed from two fundamental particles called up and down quarks. So along with electrons, all that is present can be made from up and down quarks.

But till date 12 fundamental particles have been discovered. So what are these needed for. Whether it is finally 12 or any number is also a guess because theories can get shattered by the availability of more powerful smashers.

It is known that energy and mass are the two sides of the same coin. From the mass we can create energy and vice versa. How particles get different masses?

It was proposed that space is filled with a energy field called Higgs field. If we consider it was water in a container for analogy then it is continuous with break. Water is made of molecules of water which is H2O. These molecules fill all the space occupied by water. It means water molecule is smallest unit . By analogy smallest unit of energy or the particles which make the Higgs field are called Higgs Boson. It is this field which gives the particles their different masses which represent the extent of its interaction with the field.

In the particle accelerators, atoms moving almost at 99% or more the speed of light are collided with each other. They get converted into energy field. This energy field then gets converted into numerous sub atomic particles which are recorded. It is hoped that out of these particles, the Higgs Boson will show up. At least CERN which is doing the research with giant colliders having perimeters of almost 22 kilometers announced that they have observed a particle which is most like the Higgs Boson.

Efforts will continue. Since this particle which stands as the central entity in the Standard Model which is currently the most successful system to explain the existence of the sub atomic particles, will be successfully discovered. Since it is so elusive , it has been nicknamed the “God Particle”

Changes in Periodic Table of Chemicals….

We know that everything in the universe is made from the atoms. They are the basic building entities. Atoms are not solid entities but are made of dense nuclei surrounded by fuzzy cloud of electrons whizzing in the outer. Nucleus is made of protons and neutrons. Things don’t not end here. Nature is very complex. Even the atoms of same elements can have different number of neutrons making them have different weights. Such atoms are called isotopes. Atoms of same element or different elements can combine in umpteen ways resulting in diverse molecules and different substances from very simple molecules like water and methane to complex molecules containing thousands of atoms.
Many elements have more than one isotopes. One of these is the most abundant and is for all practical purposes considered as the representative. Other isotopes exist in very low abundance. All elements can be divided into different groups in which the chemical and physical properties vary in periodic manner.
Earlier, we remember the chemical composition of compounds was determined by chemical methods using classical techniques. From the elements proportions an empirical formula was derived. Methods gave numbers of constituent elements which have to be rounded off.this happened due to the inherent limitations of determinations. So generally the molecular weights were either whole numbers or at most rounded off to first decimal place.
Thanks to the extremely accurate measurements now available with advancement of science, we are measure the abundance of all isotopes very accurately. Ten elements namely hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine and thallium which have one or more isotopes have now been selected whose atomic weights shall be displayed in the periodic table as a range. For example, the atomic weight of boron (atomic number 5) is currently written as 10.811. On the new periodic table, it will be given as an interval—from 10.806 to 10.821. This might not seem like a big change—and it is very small—but such a change can be critical to calculations in scientific research and for industrial applications. Also, chemistry teachers and students will have to learn how to use the new weight intervals.
Since now we the abundance and atomic weights of each isotope very accurately, the range will fix the upper and lower limits. By comparing the atomic weight of a particular element in a sample and mapping it on the range interval we can know the source of sample.
For example, oxygen atoms in the water samples contain isotopes. During evaporation fractionation occurs. Water molecules with lighter oxygen atoms evaporate faster leaving behind the water with heavier isotopes.
Similarly, the atomic weight of carbon is smaller in performance-enhancing drugs than in natural testosterone meaning natural testosterone contains higher abundance if heavier carbon atoms. This difference can be used to test whether athletes used these drugs to improve their performance.
The new atomic weight measurements not only account for the presence of isotopes but also consider their relative concentrations in the universe. Carbon 12 makes up 98.89% of all carbon, while carbon 13 is 1.11%, and the natural abundance of carbon 14 is 0.0000000001%. So, the weight interval for carbon will lean more heavily toward carbon 12 and range from 12.0096 to 12.0116. This range will replace the average atomic weight for carbon listed in any chemistry textbook, which is 12.011.

Unesco World Heritage tag for Rani-ki-Vav

Rani ki vav or the Queen’s Stepwell at Patan, Gujarat has been bestowed with this honor a few days back under criteria i and iv which say. First criterion is the structure represents a masterpiece of human creative genius and second criterion says the item under consideration is an outstanding example of a type of building, architectural or technological ensemble or landscape which illustrates significant stages in human history.Rani-ki-Vav (le puits à degrés de la Reine) à Patan, Gujarat

Rani-ki-Vav (the Queen’s Step well) at Patan, Gujarat is located on the banks of the Saraswati River and was initially built as a memorial to a king in the 11th century AD. Rani or the queen Udayamati commissioned this vav or step well, in 1063 in the memory of her husband King Bhimdev I of the Solanki dynasty. Rani-ki-Vav was built at the height of craftsman’s ability in step well construction and the Maru-Gurjara architectural style, reflecting mastery of this complex technique and great beauty of detail and proportions. Designed as an inverted temple highlighting the sanctity of water, it is divided into seven levels of stairs with sculptural panels of high artistic quality. The vav was later flooded by the nearby Saraswati River and silted over until the late eighties, when it was excavated by the Archaeological Survey of India, with the carvings found in pristine condition. Rani Ki Vav is among the finest step wells in India, and one of the most famous legacies of the ancient capital city.

Rani-ki-Vav (le puits à degrés de la Reine) à Patan, Gujarat

The vavs of Gujarat are not merely sites for collecting water and socializing, but also simultaneously hold great spiritual significance. They were originally constructed quite simply, but became more intricate over the years, perhaps to make explicit this ancient concept of the sanctity of water by carving it out in stone deities thus representing a subterranean temple.

The steps begin at ground level, leading you down through the cool air through several pillared pavilions to reach the deep well below. There are more than 800 elaborate sculptures among seven galleries. The central theme is the Dasavataras, or ten incarnations of Vishnu, including Buddha. The avatars are accompanied by sadhus, Brahmins, and apsaras (celestial dancers), painting their lips and adorning themselves. At water level you come to a carving of Sheshashayi-Vishnu, in which Vishnu reclines on the thousand-hooded serpent Shesha, where it is said he rests in the infinity between epochs.

The fourth level is the deepest and leads into a rectangular tank of 9.5 by 9.4 meters, at a depth of 23 meters. The well is located at the westernmost end of the property and consists of a shaft, 10 meters in diameter and 30 meters deep.

For more pictures visit the Unesco page.

Some snippets from childhood ?

I am 61 years old now and retired from the service. In the ample time at my disposal, the mind harks back and reel of memory rewinds on the spool of time and this time it stops at the days of my childhood. Our childhood was spent in the village called Manimajra. Nowadays it is in the Union territory of Chandigarh though at that time it was along with Chandigarh a part of Punjab.
We were like most others in the village poor peasants with small landholdings. Parents were totally illiterate. In those days, nobody was serious about the education and future of their children. It was supposed that they will fend for themselves when they will grow up. In all probability would be farmers like them. If they went to school it was by luck.
Even I did not like the school. There was nobody to cajole us about the need of education to become something and live comfortably. But still we went to school.
After school and taking lunch, we invariably headed for our fields which were quite far away. It was all the on foot through rough paths, streams littered with pebbles and thorny detours. We brought back the green fodder for our buffaloes.
But there were other outings also which we enjoyed most. One of these was going together to shrines of Mansa Devi which are about 4 to 5 kilometres away situated in the hillocks which are sub-systems of Shivalik hills. Usually the temples are situated in the hills.
There are two temples separated by half a kilometre distance. The lower one was constructed by the Raja of Manimajra and the other by Royal family of Patiala. The lower temple is older and was more aesthetic in design. There were frescos depicting mythological scenes related to Durga slaying the mehsasur and also of Krishna Leela. I don’t know what has become of them because even at that time they were not in well preserved condition.
There were small shrines littered around the main temples. One such was at the foot of the stairs leading to the temple. There was a big water tank in front of it. Pilgrims took bath in it during the times of annual fares in which people from Punjab, Haryana and Himachal came to participate.
Farmers usually came in groups. There was at that time fashion of carrying a stick which was specially designed with a bend at the one end. Usually there were quarrels between groups and then this weapon was used freely. These people drank the country liquor and sweets like Ladoos and Jalebis were favourite.
But this was during the fare. In other times, there were very few people and it was very peaceful. We came many a times with our grandfather who was friends with a sadhu of the shrine. As they sat chatting and smoking hookah we played there for long time.
During other times, we came with friends and headed for the area beyond the temple. There were unending clusters of thorny bushes which bore the fruit “Ber” diminutive variety of jejube. They were mostly sour and sweet. All day we ate those and collected for home. Other attraction was an army helicopter which hovered over and many a times landed in the clearings of the bushes. We were awestruck with it and the way bushes swayed when it came down.
There was another attraction. It was walking along the Chandigarh Kalka railway line which passed in that area. We always waited impatiently for the train to appear. When it came rolling like a black giant which inspired awe and fear. The engine was steam based with clouds of smoke from burning coal issuing from the exhaust. The goods train used to halt at the crossing of the road leading to the temple. Many women from nearby village came to fill pitchers of water from the engine. Sometimes the motorman also gave them the partially burnt coal for use in homes.
During winter, the cough usually pestered us. There were no of the counter medicines. There was a herb called Adusa which grew in abundance. It bore white flowers which contained a nectar which soothed the throat. We sucked them and also brought back home because the cough became acute as the temperature dropped during the night.

Such were the days. A carefree life not affected by lack of money. There was hardly any pollution. No gadget like television, radio etc which keep us engrossed at home and we miss the nature’s beauty and surprises which wait us outside.

Concept of pH in Chemistry

Although the pH of a lake or polluted stream is seldom reported in the media, the people who are monitoring the health of the lake water record it daily religiously. But pH is quite an important physical property of water. pH of a stream gives an indication about the salts and other soluble matter present in the water. These soluble salts affect the organisms living in the water. Also changing pH in a stream can be an indicator of increasing pollution or some other environmental factor.

As we know life on our planet is based on the water. Water is a unique solvent as it dissolves a number of chemicals in it. Water molecule is a simple one with H2O as its formula indicating 2 hydrogen atoms joined to 1 oxygen atom. It V shaped geometry imparts it high polarity with which it is able to break down many salt molecules into individual ions called cations and anions. As such water is slightly ionized into equivalent amounts of hydrogen and hydroxyl ions. The value is 10-07 equivalents, a very very tiny value indeed. But this small value is enough to do all the chemistry. When chemicals dissolve in it, the values of hydrogen and hydroxyl ions become unequal. Particularly when any compound containing hydrogen ions is added to water, hydrogen ions become predominant and solution is said to become acidic and such chemicals are called acids. Examples of acids are hydrochloric acid, nitric acid, citric acid and sulphuric acid. On the other hand, when any chemical which have hydroxyl ions is added to water, hydroxyl ions predominate and water becomes basic and such chemicals are called bases.  Examples of bases are sodium hydroxide, washing soda and potassium hydroxide.

pH is a measure of how acidic/basic water is. It is defined as the minus logarithm of hydrogen ions concentration. Since -log[10-07] is 7, the pH of pure water is 7. The range goes from 0-14. Any solution having pH value less than 7 is acidic and above 7 is basic in nature.

The pH of any natural water determines availability of nutrients like phosphorus, nitrogen, and carbon for aquatic life. Many nutrients like phosphorous are very sensitive to pH since it exists in different forms at different pH values. Only a particualr form is assimilated by the organism.

Similarly, pH determines the solubility of heavy metals which are generally toxic in nature. Heavy metals are generally more soluble at lower pH and hence lower pH gives a warning about the possibility of these heavier and poisonous metals.

pH of Battery acid is 1, vinegar is about 3, milk slightly above 6, baking soda between 8 and 9 & ammonia solution about 12.Diagram of pH. pH 1=battery acid, 2=lemon juice, 3-vinegar, 6.5=milk, 8.5=baking soda, sea water, 10.5=Milk of Magnesia, 12=ammonia, 13=lye. ph 3 to 4=Adult fish die. ph 4-5=Fish reproductionaffected. pH 5-6.5=Normal range for precipitat on. pH 6-8=Normal range of stream pH. pH 1-5=Acid rain.

Idyllic Life

There is a piece of uncultivated land adjacent to our building. Land is scarce in Punjab. Every inch is under cultivation. So this piece of land with uneven surface must have been purchased by some builder for construction of high rise buildings. But at present it is as it is. Grass and shrubs are growing uninterrupted in this land. On the opposite end are dense woods where poplar and eucalyptus are growing majestically. Poplars are not complicated trees. They are straight with no branches stand like the sentries at attention. The eucalyptus trees have grown so high as to touching the sky.


During day time sunlight seem to play hide and seek with the dark in the woods. Top branches sway in the wind and there seem to something mystical in these woods. Occasionally, a bunch of peahens accompanied by a peacock stray from woods into the grass fields.There is a pool of water into which these days algae has grown and covered most of its surface. Algae is pushed from one side to other when the wind blows. Sun simmers in the water ripples.  On the nearby bushes cranes are seen sitting basking in the sun occasionally diving into the water.

Paths have been trodden in the random patterns by the people going towards woods from other end. The earth on these paths have become bald and devoid of grass. The fields are not at one plain, some are on higher plane.

Many a times, sitting at my room, I can hear the calls of some bird which become quite loud and distinctive in the night. Ilapwingn the day time if you are lucky you can glimpse these birds almost running on the ground. These birds are called “Yellow Wattled Lapwings”. They lay eggs on the ground in the pebbles. If it is very hot, the birds are seen diving into the water and sitting wet on the eggs to cool them. It is believed here that if the bird lays eggs on the higher plane, the coming days will be rainy. It the eggs are laid down in lower fields, it means the coming days shall be dry.

Animals cannot digest Cellulose

Most plants synthesize cellulose which they use to give strength to their bodies and make them withstand the vagaries of storms. It gives the shape to the trees and branches then expand the tree. Cellulose becomes the wood when trees become mature. Furniture is made of this material. It is obvious that cellulose is insoluble in water otherwise no one will use it in construction and furniture.

Cellulose and starch and other carbohydrates consist of glucose molecules which are arranged in chains of different styles. In starch, two chains are intertwined. These chains get separated on boiling the starch in water. This caused the chains to disperse in the water increasing its viscosity. Such starch is called pre-gelatinized starch.

On the other hand, cellulose structure is such that chains are not dispersed and wood remains unaffected in water. Glucose is the basic unit of sugar which is used by animals like humans for obtaining energy to keep the body running.

How do then we assimilate higher sugars like starch. They have to broken down to glucose units. The enzymes found in humans and other animals allow them to digest and metabolize many, but not all, biomolecules. Cellulose is one example of a molecule that defies digestion in many animals.

But the slight difference in the way the glucose molecules are hooked together in starch compared with how they are hooked together in cellulose makes a big difference in their digestibility.

Humans and many other higher animals have the enzyme required to break the bonds in starch, releasing glucose. The particular enzyme is called alpha-amylase.But because the shape of the linkage is different in cellulose, the same enzyme will not work. In fact, where cellulose is concerned, humans do not have an enzyme that will work.

As it turns out, most humans eat a fair amount of cellulose in the form of fruits and vegetables. Although we cannot digest it, the cellulose serves as roughage or fiber that gives food bulk and keeps it moving through the digestive system. In the end, all of the undigested material ends up being eliminated as feces.

Maybe you are wondering how animals such as cattle, sheep, deer, and goats thrive on a diet of grass or other cellulose-rich food. Can they digest cellulose when humans cannot? The answer is no. None of these animals have the enzymes required to digest cellulose. Instead they rely on colonies of microorganisms living in their digestive systems.

These simple microorganisms have the correct enzymes to digest the cellulose and to reassemble the products into starches and proteins. From these products, grazing animals acquire their nutrients. The special relationship between these animals and their resident microbes is called symbiosis—two organisms living with each other to the benefit of both.

Observing the Nature

How often do we leisurely watch the nature around us? General answer will be not often. Do we sit out in the evening and watch the sun going down, its glow becoming golden, and shadows lengthening and blinking through the chinks in the trees? Do we watch the groups of birds flying towards their homes after spending their day in a far off place where the food is available to forage? Why, in the first place, they don’t make their resting places near the food. May be the supply is not available at one place throughout the year and their resting places are at optimum distance from the foraging places. Why do they always fly in the groups? Is not their pressure or competition for food? Is the father of Evolution theory listening?

After reeling under the sweltering heat for many days, if there is rain, it is like a fresh breath of life. The parched land is drenched with water pushing out the air filled with earth’s aromas into the atmosphere and filling our nostrils with ecstasy. The accompanying wind rushes into the branches which sway from side to side at the top such as in the mighty silver oak trees. One wonders how the topmost leaves are receiving their requirement of water and nutrients. In optimistic hope of supply from the soil, additionally they must be conserving the water by reducing their stomata counts, As they are in the top, they have the benefit of plenty of sunlight. I also wonder if the leaves at the top are in any sort of communication with those at the lower branches.

Rain patters on the tins of roofs. Water begins to flow over the soil surface seeking places which are at lower level to become pooled there. The dust on the leaves which was choking the plants breath is washed up and translucency returns. Sometimes after the rain, sun comes out and everything shines resplendently. The weather becomes bearable.

Chemistry behind the Color of cooked Beans

Cooked green beans can be a vivid green color, or they can turn gradually less colorful, sometimes becoming greyish or brownish.  Generally salt is added to the water before boiling vegetables. The reasons given for this include:

  • It makes them greener
  • It makes them firmer
  • It raises the boiling point of water to make them cook faster
  • It improves the flavor.

Chemists studied the truth behind these claims and found that first 3 of them are totally false. Adding salt slightly improves the flavor. The increase in the boiling point is insignificant to make any difference in the cooking time.

English: Cut Green Beans Español: Habichuelas ...

The color of the beans is dependent on the pH of the cooking water. The green color is due to chlorophyll present in the beans. If the water is acidic, the Magnesium ion bound to the chlorophyll is replaced by hydrogen ions and color is discharged. So depending upon the pH, their will be different degree of color changes.

If you cook the beans in hard water which contain bivalent ions calcium and magnesium, the pectin sugars present in the beans become firmly attached to each other and form a nice three dimensional network and give it a nice firm texture. Soft water on the other hand, dissolves the pectin quickly giving the cooked beans a mushy texture.