Chemistry - Online Test

in hybridization as % of 's'character increases electronegativity also increases.

more the s charater, more will be the electronegativity of that atom.

increasing order ofelectronegativity  with %s character is sp (50%) >  sp2(33.33%) >  sp3(25%)

Potassium is lighter than sodium (Refer table 5.3)

The correct order of density is Li < K < Na < Rb < Cs

Oxidation means addition of oxygen, removal of hydrogen, increase in oxidation number, addition of a electronegative element or removal of an electropositive element

​​​​​​The term oxidation was first used to describe chemical reactions in which oxygen was added to an element of a compound. Later on the term oxidation was extended to describe many more reactions which occurred without the use of even oxygen.

Addition of Oxygen: Oxidation is a chemical reaction in which oxygen is added to any chemical species (atom, ion or molecule). Example

2Mg + O2 → 2MgO

S + O2 → SO2

2CO + O2 → 2CO2

Na2SO3 + H2O2 → Na2SO4 + H2O

Removal of Hydrogen : Oxidation is a chemical reaction in which hydrogen is removed from any chemical species (atom, ion or molecule).

H2S + Cl2 → 2HCl + S

4HI + O2 → 2H2O + 2I2

4HI + MnO2 → MnCl2 + 2H2O + Cl2

Addition of an Electronegative Element: Oxidation is a chemical reaction in which an electronegative element is added into any chemical species (atom, ion or molecule).

Fe+ S → FeS (Oxidation of iron)

SnCl2 + Cl2→ SnCl4(Oxidation of stannous chloride)

2Fe + 3F2 → 2FeF3(Oxidation of iron)

Removal of an Electropositive Element: Oxidation is a chemical reaction in which an electropositive element is removed from any chemical species (atom, ion or molecule).

2KI + H2O2 → 2KOH + I2 (Oxidation of potassium iodide)

2K2MnO4 + Cl2 → 2KCl + 2KMnO4 (Oxidation of potassium manganate)

2KI + Cl2 → 2KCl + I2 (Oxidation of potassium iodide)

A substance which brings oxidation is known as oxidizing agentt

K_b = 0.8 × 10^–5

K_f = 1.6 × 10^–4

K_eq = K_f / K_b = 1.6X10^-4 / 0.8X10^-5 = 20