Saturday, August 12, 2017

Largest FREE Microsoft eBook Giveaway!



Microsoft Giving Away MILLIONS of FREE Microsoft eBooks again, including: Windows 10, Office 365, Office 2016, Power BI, Azure, Windows 8.1, Office 2013, SharePoint 2016, SharePoint 2013, Dynamics CRM, PowerShell, Exchange Server, System Center, Cloud, SQL Server and more!

              DOWNLOAD

Tuesday, August 1, 2017

Inorganic Chemistry, 4th edition by Catherine Housecroft, Alan G. Sharpe


                Ebook Size : 63.6 MB

                Download : Inorganic Chemistry, 4th Edition 

Inorganic chemistry: it is not an isolated branch
of chemistry. If organic chemistry is considered to be the ‘chemistry of carbon’,  then  inorganic  chemistry  is  the  chemistry  of  all elements except carbon. In its broadest sense, this is true, but  of  course  there  are  overlaps  between  branches  of chemistry. A topical example is the chemistry of the fullerenes, this  was  the  subject  of  the  award  of  the  1996  Nobel Prize in Chemistry to Professors Sir Harry Kroto, Richard Smalley   and   Robert   Curl.   An  understanding   of   such molecules, carbon nanotubes and graphene sheets involves studies by organic, inorganic and physical chemists, physicists and materials scientists.

Inorganic chemistry is not simply the study of elements and compounds; it is also the study of physical principles. For example, in order to understand why some compounds are soluble in a given solvent and others are not, we apply laws  of  thermodynamics.  If  our  aim  is  to  propose  details of  a  reaction mechanism,  then  a  knowledge  of  reaction kinetics is needed. Overlap between physical and inorganic chemistry is also significant in the study of molecular structure.  In  the  solid  state,  X-ray  diffraction  methods  are routinely used to obtain pictures of the spatial arrangements of atoms  in a  molecule  or molecular  ion.  To interpret the behaviour of molecules in solution, we use physical techniques such  as  nuclear  magnetic  resonance  (NMR)  spectroscopy;  the  equivalence or  not  of  particular  nuclei  on  a spectroscopic  timescale  may  indicate whether  a  molecule is static or undergoing a dynamic process.

The application of a wide range of physical techniques in inorganic chemistry is the topic of Chapter 4. The aims of Chapters 1 and 2 In Chapters 1 and 2, we outline some concepts fundamental to   an   understanding   of   inorganic  chemistry.   We  have assumed  that  readers  are  to  some  extent  familiar  with most of these concepts and our aim is to give a point of reference for review purposes.

An atom is the smallest unit quantity of an element that is capable of existence, either alone or in chemical combination with other atoms of the same or another element. The fundamental particles of which atoms are composed are the proton, electron and neutron.

A neutron and a proton have approximately the same mass and,  relative  to  these,  an  electron  has  negligible  mass (Table  1.1).  The  charge  on  a  proton  is  positive  and  of equal magnitude, but opposite sign, to that on a negatively charged  electron. A neutron has no charge. In an atom of any element, there are equal numbers of protons and electrons  and  so  an  atom  is  neutral.  The nucleus of  an  atom consists  of  protons  and  (with  the  exception  of protium, see  Section  10.3)  neutrons,  and  is  positively  charged;  the nucleus  of  protium  consists  of  a  single  proton.  The  electrons   occupy   a   region   of   space   around   the   nucleus.

Nearly  all  the  mass  of  an  atom  is  concentrated  in  the nucleus,  but  the  volume  of  the  nucleus  is  only  a  tiny fraction  of  that  of  the  atom;  the radius  of  the  nucleus  is about  10 15m  while  the  atom  itself  is  about  10^5 times larger  than  this.  It  follows  that  the  density  of  the  nucleus is enormous, more than 10^12 times that of the metal Pb. Although   chemists   tend   to   consider   the   electron, proton  and  neutron  as  the  fundamental  (or  elementary) particles of an atom, particle physicists deal with yet smaller particles.

Monday, June 5, 2017

Organic Chemistry, 2 edition by Jonathan Clayden, Nick Greeves and Stuart Warren


                    Ebook Size : 15.3 MB

                    Download : Organic Chemistry, 2nd edition

Organic chemistry and you You are already a highly skilled organic chemist. As you read these words, your eyes are using an organic compound (retinal) to convert visible light into nerve impulses. When you picked up this book, your muscles were doing chemical reactions on sugars to give you the energy you needed. As you understand, gaps between your brain cells are being bridged by simple organic molecules (neurotransmitter amines) so that nerve impulses can be passed around your brain. And you did all that without consciously thinking about it. You do not yet understand these processes in your mind as well as you can carry them out in your brain and body. You are not alone there. No organic chemist, however brilliant, understands the detailed chemical working of the human mind or body very well.

We, the authors, include ourselves in this generalization, but we are going to show you in this book what enormous strides have been taken in the understanding of organic chemistry since the science came into being in the early years of the nineteenth century. Organic chemistry began as a tentative attempt to understand the chemistry of life. It has grown into the confident basis of worldwide  activities that feed, clothe, and cure millions of people without their even being aware of the role of chemistry in their lives. Chemists cooperate with physicists and mathematicians to understand how molecules behave and with biologists to understand how interactions between molecules underlie all of life. The enlightenment brought by chemistry in the twentieth century amounted to a revolution in our understanding of the molecular world, but in these first decades of the twenty-first century the revolution is still far from complete. We aim not to give you the measurements of the skeleton of a dead science but to equip you to understand the conflicting demands of an adolescent one.

Like all sciences, chemistry has a unique place in our pattern of understanding of the universe. It is the science of molecules. But organic chemistry is something more. It literally creates itself as it grows. Of course we need to study the molecules of nature both because they are interesting in their own right and because their functions are important to our lives. Organic chemistry has always been able to illuminate the mechanisms of life by making new molecules that give information not available from the molecules actually present in living things. This creation of new molecules has given us new materials such as plastics to make things with, new dyes to colour our clothes, new perfumes to wear, new drugs to cure diseases. Some people think some of these activities are unnatural and their products dangerous or unwholesome. But these new molecules are built by humans from other molecules found naturally on earth using the skills inherent in our natural brains. Birds build nests; people build houses. Which is unnatural? To the organic chemist this is a meaningless distinction. There are toxic compounds and nutritious ones, stable compounds and reactive ones—but there is only one type of chemistry: it goes on both inside our brains and bodies, and also in our flasks and reactors, born from the ideas in our minds and the skill in our hands. We are not going to set ourselves up as moral judges in any way. We believe it is right to try and understand the world about us as best we can and to use that understanding creatively. This is what we want to share with you.

Sunday, June 4, 2017

The Demon Haunted World - Carl Sagan


                 
                       Ebook Size : 4.4 MB

                       Download : The Demon Haunted World - Carl Sagan

    "SCIENCE AS A CANDLE IN THE DARK"

It was a blustery fall day in 1939. In the streets outside the apartment building, fallen leaves were swirling in little whirl winds, each with a life of its own. It was good to be inside and warm and safe, with my mother preparing dinner in the next room. In our apartment there were no older kids who picked on you for no reason. Just the week before, I had been in a fight – I can't remember, after all these years, who it was with; maybe it was Snoony Agata from the third floor - and, after a wild swing, I found I had put my fist through the plate glass window of Schechter's drug store.

Mr Schechter was solicitous: 'It's all right, I'm insured,' he said as he put some unbelievably painful antiseptic on my wrist. My mother took me to the doctor whose office was on the ground floor of our building. With a pair of tweezers, he pulled out a fragment of glass. Using needle and thread, he sewed two stitches.

'Two stitches!' my father had repeated later that night. He knew about stitches, because he was a cutter in the garment industry; his job was to use a very scary power saw to cut out patterns - backs, say, or sleeves for ladies' coats and suits - from an enormous stack of cloth. Then the patterns were conveyed to endless rows of women sitting at sewing machines. He was pleased I had gotten angry enough to overcome a natural timidity. Sometimes it was good to fight back. I hadn't planned to do anything violent. It just happened. One moment Snoony was pushing me and the next moment my fist was through Mr Schechter's window. I had injured my wrist, generated an unexpected medical expense, broken a plate glass window, and no one was mad at me. As for Snoony, he was more friendly than ever.

I puzzled over what the lesson was. But it was much more pleasant to work it out up here in the warmth of the apartment, gazing out through the living-room window into Lower New York Bay, than to risk some new misadventure on the streets below. As she often did, my mother had changed her clothes and made up her face in anticipation of my father's arrival. We talked about my fight with Snoony. The Sun was almost setting and together we looked out across the choppy waters. 'There are people fighting out there, killing each other,' she said, waving vaguely across the Atlantic. I peered intently. 'I know,' I replied. 'I can see them.' 'No, you can't,' she replied, sceptically, almost severely, before returning to the kitchen. 'They're too far away.'

How could she know whether I could see them or not? I wondered. Squinting, I had thought I'd made out a thin strip of land at the horizon on which tiny figures were pushing and shoving and duelling with swords as they did in my comic books. But maybe she was right. Maybe it had just been my imagination, a little like the midnight monsters that still, on occasion, awakened me from a deep sleep, my pyjamas drenched in sweat, my heart pounding.

How can you tell when someone is only imagining? I gazed out across the grey waters until night fell and I was called to wash my hands for dinner. When he came home, my father swooped me up in his arms. I could feel the cold of the outside world against his one-day growth of beard. On a Sunday in that same year, my father had patiently explained to me about zero as a placeholder in arithmetic, about the wicked-sounding names of big numbers, and about how there's no biggest number ('You can always add one,' he pointed out). Suddenly, I was seized by a childish compulsion to write in sequence all the integers from 1 to 1,000. We had no pads of paper, but my father offered up the stack of grey cardboards he had been saving from when his shirts were sent to the laundry.