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Depression in Freezing point and Elevation in Boiling point

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Depression in Freezing Point: Depression in freezing point means freezing point of solution is always less than that of its pure solvent due to lowering of vapour pressure of solution. Depression in freezing point have the formula as given below, ∆T f = i × K f × m                                       eq.. (1) K f = cryoscopic constant This equation tells us that depression of freezing point depends only on   molality of solutions, so it is a colligative property. m= 1000W 2 /W 1 ×M 2                           putting the value of molality in we get          ∆T f   = i × K f × 1000W 2 /W 1 ×M 2        ...
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Balancing Redox Reactions Oxidation number method(part2)

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  How to balance redox reactions by Oxidation number method? Balancing Redox Reactions by Oxidation number method: The key to the oxidation number method of balancing redox reactions is to realize that net change in the total of all oxidation numbers must be zero. Any increase in oxidation number for the oxidized atoms must be matched by corresponding decrease in oxidation state for the reduced atoms. Following are the steps for balancing redox reactions by oxidation number method: 1.     1.   Write down the skeletal equation of redox reaction. Let’s take the following reaction for example Br 2 + NaOH→ NaBr + NaBrO 3 + H 2 O 2.     2 .  Assign oxidation number to all atoms including O and H atoms if present in both reactants and products. Br 2 + NaOH→ NaBr + NaBrO 3 + H 2 O ↑       ↑    ↑   ↑        ↑    ↑       ↑ ↑   ↑ ...
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Balancing Redox Reactions by Ion-Electron method(part1)

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  How to balance redox reactions? How can we balance redox reactions by Ion-Electron method? Balancing redox reactions: The balancing of redox equations by the loss and gain of electrons, usually involves quite a few ions, which do not undergo change in valence and which are not necessary for the process of balancing. The ion –electron method eliminates a unnecessary ions and retains only those, which are essential. Following are the general rules for balancing redox equations by ion- electron method. 1.    Assign oxidation states to determine species being oxidized and reduced, and write the half reactions. 2.    Balance each half reaction. a.    Balance the atoms being oxidized or reduced. b.    Balance oxidation number by adding electrons. c.    Balance the other elements that are present, for example S with SO 4 2- or Cl with Cl 1- . d.    Balance oxygen atoms by adding H 2 O. e.    Balan...
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Paramagnetic, Diamagnetic, Ferromagnetic, Antiferromagnetic and Ferrimagnetic behavior of substances

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What is Paramagnetic, Diamagnetic, Ferromagnetic, Antiferromagnetic and Ferrimagnetic behavior of substances? What is the effect of temperature on these properties? Paramagnetic substances: These substances are attracted by the magnetic field and have unpaired electrons. These lose magnetism in the absence of magnetic field. Some examples of paramagnetic substances are transition metals like Cr, Mn, Co, Fe and metal oxides like CuO,VO 2 . Diamagnetic substances: These substances are weakly repelled by magnetic field and have no unpaired electrons. Some examples of diamagnetic substances are H 2 O, benzene, NaCl, TiO 2 . Ferromagnetic substances: Such substances are strongly attracted by magnetic field. In the absence of magnetic field magnetic field these substances have magnetic domains randomly oriented in such a way that their overall magnetic moment gets cancelled. But in the presence of magnetic field they are oriented in such a way that they together produce a str...
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Slater's Rule

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         What is Slater's Rule and its significance? How to calculate value of σ  and Zeff using Slater' Rule: Slater's Rule : Slater’s rules are a set of empirical guidelines used to calculate the shielding constant (σ) and the effective nuclear charge (Zeff) experienced by an electron in a multi-electron atom. They were introduced by John C. Slater to simplify the complex quantum mechanical interactions between electrons. These rules estimate how much the inner electrons reduce the attractive force of the nucleus on outer electrons. Mathematically:                              Zeff=Z−S where: Z = atomic number (total nuclear charge)             S = shielding constant (calculated using Slater’s rules Significance of Slater's Rule: To quanti...
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