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In the reactant; Cu\(_2\)S 2 Cu - 2(1) = 0 2 Cu = 2 Cu = \(\frac{2}{2}\) Cu = +1 In the product, Cu Cu = O (Oxidation state of an element in its free state is 0) The oxidation number of Cu in Cu\(_2\)S and Cu respectively is +1 and 0 respectively

The setup represents the production of sulfur dioxide. And the cylinder marked X is SO2

In the preparation of sulphur dioxide by the action of dilute acids on sulphates and bisulphites. conc H2SO4 helps to release SO2 from the mixture. The setup represents the production of sulphur dioxide

M = \(\frac{\text{Molar mass × Quantity of Electricity}}{\text{96500 × no of charge}}\) = \(\frac{MmIT}{96500n}\) Copper II Chloride = CuCl2 CuCl2 → Cu2+ + 2Cl2 Mass of compound deposited = \(\frac{\text{Molar mass × Quantity of Electricity}}{\text{96500 × no of charge}}\) Q = IT I = 0.5A T = 45 × 60 T = 2700s Q = 0.5 × 2700 = 1350c Molarmass = 64gmol-1 no of charge = + 2 Mass = \(\frac{64 \times 1350}{96500 \times 2}\) Mass = 0.448g

CH2CH2 - CCH3CH2 Start the numbering from the terminal carbon.

An element's chemical properties depend on its valence electrons.The chemical properties of elements depend on an element's electron configuration.

Test tubes are convenient containers for heating small amounts of liquids or solids with a Bunsen burner or alcohol burner.

Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers.

Scandium has electronic configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{1}4s^{2}\) hence, \(Sc^{3+}\) has configuration \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}\). Hence, no electron in the 3d-orbital.

The various gases vaporize as their boiling points are reached, then they are pumped away and separately re-liquefied for convenient storage.

The purity of a solid can be determined by measuring the melting point. A pure solid will have a single, sharp melting point.

This is same as asking for the molar mass of the compound = \((2\times 14.0)+ (8\times 1.0) + 12.0+(16.0\times 3)\) = 28.0+8.0+12.0+48.0 = 96.0g

The orbital is a path or region around the nucleus. The electrons move in the orbitals and not through it.

The ionic radius decreases across a period but increases along a group.

This is caused by the increase in the number of protons and electrons across a period.