A small proportion of the universe is made up of matter and the matter is mostly made up of atoms. Atoms consist of
three basic sub particles: protons, neutrons and electrons. Note: If these particles were not there, there would be neither i and you nor the physical universe.
Particle Mass kg Me V/c 2 Charge C
Electron 9.109 x 10-31 0.511 -1.602 x10-19
Proton 1.672 x 10-27 938.28 +1.602 x10-19
Neutron 1.675 x 10-27 940.60 0
Energy is the ability to work. Look, how different types of energy are produced by atomic particles:
Electrical energy is due to motion of electrons.
Light energy is due to photons emitted by hot objects like the sun, bulbs etc.
Thermal energy is due to vibration of atomic particles within substance.
Sound Energy is caused by the vibrations of atomic particles in air.
Chemical energy is a stored in the bonds of atoms and is released as the bonds are broken.
Nuclear energy is present in the bonds that hold the nucleons in the nucleus together by gluons.
god energy in general is the mother of all creation through elementary and atomic particles.
Chemical reaction is a reaction in which outermost electrons take part.
Look, how does the transfer of one electron bring a big change! In all chemical reactions the outermost negatively
charged electrons of an atom take part. When Na atom reacts with Cl atom, sodium atom loses its outermost electron and becomes positively charged and Chlorine by gaining one electron becomes negatively charged. The Na+ and Cl– ions are held together by electrostatic forces thus forming ionic bonds. Note, Sodium is a silver alkali metal and chlorine is a poisonous gas. When chemically bonded together, these two dangerous substances form a compound sodium chloride (table salt), so safe that we eat it every day. Q.How,things changed?
Isotopes
Look, how the addition of neutrons changes the nature of isotopes! Isotopes of a given element have the same
number of protons, but different numbers of neutrons in their atom.Chemical properties of isotopes are the same as they all have the same number of electrons, but physical and nuclear properties are different as they have different number of nucleons (protons + neutrons) in the nucleus. Hydrogen has three main isotopes:
Protium (1H) is an ordinary hydrogen. It is the lightest of all isotopes, It is highly reactive and found as H2. It is a stable isotope of hydrogen.
Deuterium (2H) is heavier than protium and found in heavy water. It reacts more slowly than protium. It is also a stable.
Tritium (3H) is the heaviest, unstable and only radioactive isotope of hydrogen.
Allotropy
Look, how the same number of atoms with different geometric arrangement changes the nature of material! Some elements exist in two or more different physical forms with different arrangements of their atoms having the same chemical properties but different physical properties. They are called allotropic forms like the diamond & graphite. Both are made of carbon atoms, but their atoms are arranged in different ways. They have the same chemical properties, but different physical properties.
In diamond each carbon atom is bonded to other 4 carbon atoms by strong covalent bonds.The diamond has a tetrahedral structure that makes it the hardest substance; it is transparent, brilliant and the most expensive material. It is a poor conductor of electricity as there are no free electrons to move.
In graphite each carbon atom is bonded to three other carbon atoms and the fourth bond of each carbon atom is
between the layers. It occurs in hexagonal layers stacked one on top of the other. The layers slip easily one over the other. Between the layers the bonding forces are very weak.That explains why graphite is soft and slippery to touch.
Nuclear fusion reaction is that in which nucleons take part.
Look, how the hydrogen atoms release an enormous amount of energy in the sun to sustain life on earth!
How do the stars shine? The answer is the nuclear fusion reactions that take place in the core of the sun at + 10
million degree Celsius because a great deal of energy is needed to overcome the force of repulsion between positively charged nuclei. In this process two light nuclei fuse each other to form a single heavier nucleus.
Reaction and energy calculation
2/1 H + 3/1 H > 4/2 H + 1/0 n
2.013553 + 3.016049 > 4.001506 + 1.008665 amu
5.029602 amu > 5.010171 amu
Mass defect = mass of reactants – mass of products = 5.010171- 5.029602 = 0.019431 amu. As 1 amu = 1.661 x 10 e -27 (kg), therefore 0.019431 amu = 3.23 x 10 e -29 kg.
According to E= mc2, E= 3.23 x 10 e -29 kg X (3.0 10 e 8 M/s)2 = 2.91 X 10 e -12 Joule = 18.2 MeV. This is the energy released in the fusion of one helium nucleus. The energy we receive as light and heat. It is essential for all forms of life (plants and animals).
Q. Is it a Chance or Choice ?
Nuclear Fission
Look, how big energy is contained in the core of Uranium atoms? In nuclear reactions, the particles within the nucleus
take part i.e., protons and neutrons like in the Uranium 235. When Uranium 235 nucleus absorbs an extra slow moving neutron, it becomes unstable and quickly splits into lighter nuclei (barium and krypton) plus 2 to 3 neutrons plus releasing large amount of energy in the form of radiations and kinetic energy due to the motion of fragments and free neutrons.
Reaction and energy calculation
U235 + 0n1 → 56Ba141 + 36Kr92 + 3 (0n1)
235.0439 + 1.008665 > 140.9114 + 91.92616 + 3.025995 (One amu = one twelfth of the mass of 12C atom)
Mass defect = Mass of reactants 236.0525 – Mass of products 235.8666 = 0.1859 amu (As 1 amu = 1.661 x 10 e-27 kg, therefore mass defect 0.1859 amu x 1.661 x 10 e -27 kg = 3.09 x10 e -28 kg,
According to Albert Einstein equation E = m c2 , the mass defect is converted into energy as follows: E = 3.09 x10 e-28 kg * (3×108 m/s) 2 = 2.78 x 10e -11 Joule As 1.602 x 10 e -13 joules = 1 (MeV), therefore 2.78 x 10e -11 Joule = 174 MeV is the energy released per fission of one atom of Uranium 235
Divide Avogadro constant number by the atomic mass of U-235 to find the number of atoms of U-235 in one gram. So Uranium-235 contains 6.022×1023 / 235 = about 2.5×1021 atoms per gram. Energy released by I gram of U235 = 8.202×10e10 J or simply 13.46 barrels of oil.
Q. Look, the amount of energy generated from one gram of an uranium atom?
Number of energy levels
Look, how the number of energy levels changes the nature of a material. Oxygen has two energy levels whereas sulfur three. Oxygen is therefore smaller and more electronegative (ability to attract electrons) than sulfur. Therefore the oxygen in H2O attracts the lone pair of electrons more than sulfur in H₂S which makes oxygen partial negative and hydrogen partial positive and hence makes hydrogen bonding as shown in figure. Because of hydrogen bonding, water is a drinking liquid and vital for all forms of life while H₂S without hydrogen bonding is a gas with a rotten egg smell and is dangerous for health.
Q. Is it not incredible?
How air, water and food sustain life on earth
Air by volume contains 78.09% nitrogen, 20.95% oxygen, 0.93% argon, 0.04% carbon dioxide, and small amounts of other gasses and variable amount of water vapor. Air is a mixture of gasses and gasses are made up of these atomic particles.
Note, Oxygen is non- living, but vital for life.
Water Remember 3/4 of the earth and 2/3 of a human body is water. The chemical formula of water is H2O, meaning that it contains one oxygen and two hydrogen atoms that are connected by a strong covalent bond. We actually drink water molecules in the liquid form.
It is colorless because it reflects all light except a tiny bit of blue.
It is tasteless because it does not chemically react with our test receptor cells.
It is odorless because we don’t have those receptors in our nose to smell it.
Food is usually of plant and animal origin and contains essential nutrients such as carbohydrates, proteins, vitamins, or minerals and many others. All are made of atomic particles (atoms). Carbohydrates are made up of carbon, hydrogen and oxygen. It provides energy.
Proteins are composed of different arrangements of amino acids. Proteins are made up of carbon (54%), hydrogen (7%), nitrogen (16%), oxygen (22%) and some may contain sulfur (1%) and phosphorus (0.6%). Proteins accelerate the rate of metabolic reactions and perform hereditary transmission.
Minerals, like calcium, magnesium, potassium, sodium, sulfur, iron, cobalt, copper, zinc, iodine, fluorine, manganese and many others perform different functions in the body.
Note, A normal person can’t survive more than 3 minutes without oxygen, 3 days without water and 3 weeks without food. We inhale atoms, we drink atoms and we eat atoms by which we sustain our lives. All these are non living things, but vital for all forms of life.