what are some important problems for molality concept

Problems based and asked on all the concepts covered in the chapter are important.

Given below are some important formulae which will help you in solving the problems.

Relative molecular mass of a gas or vapour = 2 × VD

Mole and Gram Atomic Mass: One mole of atoms = 6.022 ×1023 atoms                                                                                 = Gram atomic mass of an element                                                                                 = 1 gram atom of the element
Mole and Gram Molecular Mass: One mole of molecules = 6.022 ×1023 molecules                                                                                            = Gram molecular mass                                                                                            = 1 gram molecule of the compound
Mole in terms of volume:               One mole of a gas        = 22.4 litres at S.T.P.
Moles of an element = Mass of the element                                    Atomic mass or GA.W	Moles of a compound = Mass of the compound                                      Molecular mass or GMW
Mass of one atom = Atomic Mass or GAW                                       6.022 × 1023	Mass of one molecule = Molecular Mass or GAW                                              6.022 × 1023
Number of molecules = Moles × 6.022 ×1023	Number of atoms = Moles × 6.022 ×1023