Fun with Chemistry

It involves the inter- change of oxygen between the elemental form of gaseous O2, contained in a huge reservoir in the atmosphere, and chemically bound O in CO2, H2O, minerals, and organic matter. It is strongly tied with other elemental cycles, particularly the carbon cycle. Elemental oxygen becomes chemically bound by various energy-yielding processes, particularly combustion and metabolic processes in organisms. It is released in photosynthesis. This element readily combines with and oxidizes other species such as carbon in the process of aerobic respiration, or carbon and hydrogen in the combustion of fossil fuels such as methane: CH4 +  2O2    →   CO2    +  2H2O Elemental oxygen also oxidizes inorganic substances such as iron(II) in minerals: 4FeO4   +   O2   →    2Fe3O3 A particularly important aspect of the oxygen cycle is stratospheric ozone O3. A relatively small concentration of ozone in the strato...

 Nitrogen occurs prominently in all the spheres of the environment. The atmosphere is 78% elemental nitrogen, N2, by volume and comprises an inexhaustible reservoir of this essential element. Nitrogen, although constituting much less of biomass than carbon or oxygenoxygen, is an essential constituent of proteins. The N2 molecule is very stable so that breaking it down into atoms that can be incorporated with inorganic and organic chemical forms of nitrogen is the limit- ing step in the nitrogen cycle. This does occur by highly energetic processes in lightning discharges that produce nitrogen oxides. Elemental nitrogen is also incorporated into chemically bound forms. or fixed by biochemical processes mediated by microorganisms. The biological nitrogen is mineral- ized to the inorganic form during the decay of biomass. Large quantities of nitrogen are fixed synthetically under high-temperature and high-pressure conditions according to the following over- all reaction:     ...

CARBON CYCLE: Carbon circulates through the carbon cycle. It shows that carbon may be pres- ent as gaseous atmospheric CO2 constituting a relatively small but highly significant portion of global carbon. Some of the carbon is dissolved in surface water and groundwater as HCO-3 or molecular CO2 (aq). A very large amount of carbon is present in minerals, particularly magnesium and calcium carbonates such as CaCO3. Photosynthesis fixes inorganic C as biological carbon. represented as (CH2O), which is a constituent of all life molecules. Another fraction of carbon is fixed as petroleum and natural gas, with a much larger amount as hydrocarbonaceous kerogen (the organic matter in oil shale), coal, and lignite. Manufacturing processes are used to convert hydro- carbons to xenobiotic compounds with functional groups containing halogens, oxygen, nitrogen, phosphorus, or sulfur. Although a very small amount of total environmental carbon, these com- pounds are particularly significant because of...

 Very much connected with environmental chemistry, cycles of matter, often based on elemental cycles, are of utmost importance in the environment. Global geochemical cycles can be regarded from the viewpoint of various reservoirs, such as oceans, sediments, and the atmosphere, connected by conduits through which matter moves continuously among the hydrosphere, atmosphere, geo- sphere, biosphere, and, increasingly, the anthrosphere. The movement of a specific kind of matter between two particular reservoirs may be reversible or irreversible. The fluxes of movement for particular kinds of matter vary greatly as do the contents of such matter in a specified reservoir. Most cycles of matter have a strong biotic component, especially through the biochemical processesof plants and microorganisms. The cycles in which organisms participate are called biogeochemical cycles, which describe the circulation of matter, particularly plant and animal nutrients, through ecosystems. Most biogeoche...

 Hello readers!  I hope you all doing well. Today we will discuss something about environmental chemistry.  The environment is defined as consisting of five spheres: the hydrosphere, the atmo- sphere, the geosphere, the biosphere, and the anthrosphere; that is, water, air, the Earth, life, and those parts of the environment consisting of human constructs and activities. The chemistry of the environment, environmental chemistry, may be defined as the study of the sources, reactions, trans- port, effects, and fates of chemical species in the hydrosphere, the atmosphere, the geosphere, and the anthrosphere and the effects of human activities thereon. The pollutant sulfur dioxide is generated during the combustion of sulfur in coal, transported to the atmosphere with flue gas, and oxidized by chemical and photochemical processes to sulfuric acid. Sulfuric acid, in turn, falls as acidic precipitation, where it may have detrimental effects such as toxic effects on trees and oth...

Bohr's Atomic Theory: Keeping in view the defects in Rutherford's Atomic Model, Neil Bohr presented another model of atom in 1913.The Quantum Theory of Max Planck was used as foundation for this model. According to Bohr's model, revolving electron in an atom does not absorb or emit energy continuously. The energy of a revolving electron is 'quantized' as it revolves only in orbits of fixed energy, called 'energy levels' by him.  The Bohr's atomic model was based upon the following postulates: i. The hydrogen atom consists of a tiny nucleus and electrons are revolving in one of circular orbits of radius ‘r’ around the nucleus. ii. Each orbit has a fixed energy that is quantized.  iii. As long as electron remains in a particular orbit, it does not radiate or absorb energy. The energy is emitted or absorbed only when an electron jumps from one orbit to another. iv. When an electron jumps from lower orbit to higher orbit, it absorbs energy and when it jumps ...

 Rutherford's Atomic Model: Rutherford performed 'Gold Foil' experiment to understand how negative and positive charges could coexist in an atom. He bombarded alpha particles on a 0.00004  cm thick gold foil. Alpha particles are emitted by radioactive elements like radium and polonium. These are actually helium nuclei (He2+). They can penetrate through matter to some extent. He observed the effects of α-particles on a photographic plate or a screen coated with zinc sulphide. He proved that the 'plum-pudding' model of the atom was not correct.  Observations made by Rutherford were as follows: i.Almost all the particles passed through the foil un-deflected. ii.Out of 20000 particles, only a few were deflected at fairly large angles and very few bounced back on hitting the gold foil. Results of the experiment: Keeping in view the experiment, Rutherford proposed planetary model for an atom and concluded following results: i.Since most of the particles passed through th...

 Discovery of Neutron: Rutherford observed that atomic mass of the element could not be explained onvthe basis of the masses of electron and proton only. He predicted in 1920 that some neutral particle having mass equal to that of proton must be present in an atom. Thus scientists were in search of such a neutral particle. Eventually in 1932 Chadwick discovered neutron, when he bombarded alpha particles on a beryllium target. Hobserved that highly penetrating radiations were produced. These radiations were calleneutron. Properties of neutron are as following: i. Neutrons carry no charge i.e. they are neutral. ii. They are highly penetrating. iii. Mass of these particles was nearly equal to the mass of a proton.

 Discovery of Proton: In 1886 Goldstein observed that in addition to cathode rays, other rays were also present in the discharge tube. These rays were traveling in opposite direction to cathode rays. He used a discharge tube having perforated cathode. He found that these rays passed through holes present in the cathode and produced a glow on the walls of the discharge tube. He called these rays as "canal rays". The properties of these rays were as following: i. These rays travel in straight lines in a direction opposite to the cathode rays. ii. Their deflection in electric and magnetic field proved that these are positively charged.  iii. The nature of canal rays depends upon the nature of gas, present in the discharge tube. iv. These rays do not originate from the anode. In fact these rays are produced when the cathode rays or electrons collide with the residual gas molecules present in the discharge tube and ionize them as follows: v. Mass of these particles was found equal...

 Even as scientists were confirming the existence of the atoms, they discovered another layer of complexity below atoms. Atoms are made of still smaller particles. Studies of electricity suggested there needed to be something that you could transfer, that carried charge. It was the work of J.J. Thomson, Ernest Rutherford among others that led to advancements in our knowledge of atomic structure. According to Dalton, an atom is an indivisible, hard,dense sphere. Atoms of the same element are alike. They combine in different ways to form compounds. In the light of Dalton's atomic theory, scientists performed a series of experiments. But in the late 1800's and early 1900's, scientists discovered new subatomic particles.  •In 1886, Goldstein discovered positively charged particles called protons.  •In 1897, J.J. Thomson found in an atom, the negatively charged particles known as electrons. It was established that electrons and protons are fundamental particles of matter. Base...

 Hello readers! I hope you all will be fine and enjoying my blogs. Today we discuss about Avogadro's number.  Avogadro's Number is a collection of 6.02×10 ²³  particles.It is represented by symbol 'NA'. Hence, the 6.02×10 ²³  number of atoms, molecules or formula units is called Avogadro's number that is equivalent to one 'mole' of respective substance. In simple words, 6.02×10 ²³  particles are equal to one mole as twelve eggs are equal to one dozen. To understand the relationship between the Avogadro's number and the mole of a substance let us consider a few examples. i.6.02×10 ²³  atoms of carbon are equivalent to one mole of carbon. ii. 6.02×10 ²³  molecules of H2O are equivalent to one mole of water. iii. 6.02×10 ²³  formula units of NaCl are equivalent to one mole of sodium chloride.  Thus, 6.02×10 ²³  atoms of elements or 6.02×10 ²³  molecules of molecular substance or 6.02×10 ²³  formula units of ionic compounds are equ...

 A mole is defined as the amount(mass) of a substance that contains  6.022 × 10²³ number of particles (atoms, molecules or formula units). It establishes a link between mass of a substance and number of particles as shown in summary of molar calculations. •It is abbreviated as 'mol'. Mass of a substance is either one of the following: atomic mass, molecular mass or formula mass. These masses are expressed in atomic mass units (amu). But when these masses are expressed in grams, they are called as molar masses.  •Scientists have agreed that Avogadro's number of particles are present in one molar mass of a substance. Thus, quantitative definition of mole is the atomic mass, molecular mass or formula mass of a substance expressed in grams is called mole. For example: Atomic mass of carbon expressed as 12 g = 1 mol of carbon Molecular mass of H2O expressed as 18 g = 1 mol of water Molecular mass of H2SO4 expressed as 98 g = 1 mol of H2SO4 Formula mass of NaCl expressed as 58....

 A molecule is formed by the chemical combinations of atoms. It is the smallest unitbof a substance. It shows all the properties of the substance and can exist independently. There are different types of molecules depending upon the number and types of atoms combining. A few types are discussed here. Monoatomic Molecules: A molecule consisting of only one atom is called monoatomic molecule. For example, the inert gases helium, neon and argon all exist independently in atomic form and they are called monoatomic molecules. Diatomic Molecules: If a molecule consists of two atoms, it is called diatomic molecule. For example: hydrogen (H ), oxygen (O2), chlorine (Cl ) and hydrogen chloride (HCl). Triatomic Molecules: If it consists of three atoms, it is called triatomic molecule. For example :H2O and CO2.  Poly atomic Molecules: If a molecule consists of many atoms, it is called polyatomic. For example: methane (CH4), sulphuric acid (H2SO4 ) and glucose (C6H12O6).  Homoatom...

  Hello! Welcome to my blog. Today we will discuss about chemical species. lets start. If one  molecule  is identical to another, we can say they are the same chemical species. Ion: It is an atom or group of atoms having a charge on it. The charge may be positive or negative.  There are two types of ions:       Cations: An atom or group of atoms having positive charge on it is called cation. They are formed when atoms lose electron from their valance shells. Examples:   Ca 2+   Ag +    Al 3+     H 3 O +     NH 4 +     Hg 2 +2      Fe +2     Fe  +3        Anions: An atom or group of atoms having negative charge on it is called anion. They are formed by gain or addition of electron to an atom. Examples: Cl –    OH –      I –     Cr 2 O 7 -2     O -2      SO ...

 Hello!  How are you all?  Today we will discuss molecular mass and formula mass.  Molecular Mass: The sum of atomic masses of all the atoms present in one molecule of a molecular substance, is it's molecular mass.  For example: molecular mass of water is 18 amu, chlorine is 71 amu and carbon dioxide is 44 amu.  Formula Mass: The sum of atomic masses of all the atoms present in one formula unit of a substance.  For example: formula mass of sodium chloride is 58.5 amu and that of CaCO3 is 100 amu.  So this was the short introduction of basic terms. See you soon. Stay tuned. 

 Hello Everyone!  Today we will discuss chemical formula. Let's start.  Chemical formulas are of two types: 1-Emperical Formula 2-Molecular Formula Empirical Formula: It is defined as the formula that shows the ratio of elements present in a compound, but not the actual numbers of atoms found in the molecule. It is also known as simple formula in chemistry.  Molecular Formula: It gives the total number of atoms of each element in each molecule of a substance.  This was the short intro of the basic terms.  Hope you get clear. 

 Hello readers! Hope you will be fine. Our today's topic is relative atomic mass. let's start! It is the average mass of the atoms of that element as compared to1/12th the mass of an atom of carbon-12 isotope. Based on carbon-12 as a standard, the mass of an atom of carbon is 12 units and 1/12th of it comes to be 1 unit. When we compare atomic masses of other elements with atomic masses of carbon-12 atom, they are expressed as relative atomic masses of those elements. The unit of relative atomic mass unit is amu (Atomic mass unit). One atomic mass unit is 1/12th the mass of one atom of carbon-12.  This was the short intro of Relative atomic mass.  See you next with another topic. Thank you!

 Hello My dear Readers!  Hopefully you all are fine and also doing experiments in your life. Let's start our today's topic. Today we will discuss atomic number and mass number.  Atomic number: The number of protons present in the nucleus of its atom is called atomic number. Atomic number is represented by 'Z'. All the atoms of an element have same number of protons in their nuclei so thay have same atomic number. Each individual element has specific atomic number that is called identification number. For example hydrogen have 1 proton so it's atomic number is Z=1. In oxygen all atoms have 8 protons, have atomic number Z=8 .  Mass number: It is the sum of number of protons and number of neutrons present in the nucleus of an atom. It is represented by 'A'.  It is calculated as:         A=Z+n Where n is number of neutrons.  For example: hydrogen atom has on proton and no neutron in its nucleus, its mass number A = 1 + 0 = 1 . Carbon atom h...

 Hello everyone!  Today we will dicuss classification of matter.  A piece of matter in pure form is called a Substance. While impure matter is called Mixture.  Further Substance is divided into element and compound. Similarly, Mixtures are of two types homogenous mixture and heterogeneous mixture.  Substance: Element: According to modern definition of element "it is a substance made up of same types of atoms, having same atomic number and cannot be decomposed into simple substance by ordinary chemical means. It means that each element is made up of unique type of atoms that have very specific properties.  Elements occur in free state as well as in combined state. They may be solid, liquid or gas.  Compound: It is a substance made up of two or more elements chemically combined together in fix ratio by mass. As a result of this elements lose their own properties and produce new substances that have different properties Mixture: Homogenous mixture: ...

 Hello!  How are you all? Today our topic is Atom.  We all heard about atom.  The smallest particle of an element is called atom. Atoms are the basic building blocks of matter. Anything that takes up space and anything with mass is made of atom.  An atom is a particular of matter that uniquely defines a chemical element. An atom consist of a central nucleus that is surrounded by one or more relatively heavy particles known as proton and neutron.    This was the short introduction of atom. Next we will discuss structure of atom.  Structure of Atom: The total mass of an atom, including the protons, neutrons and electrons, is the atomic mass or atomic weight. The atomic mass or weight is measured in atomic mass units. Electrons contribute only a tiny part to the mass of the atomic structure, however, they play an important role in the chemical reactions that create molecules. The atomic weight can be thought of as the number of protons plus the numbe...