Fun with Chemistry

 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. Based

 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 equivalent to 1 mole.

 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 58.5

 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).  Homoatomic Molecules: