question_answer

  (a) Calculate the number of atoms of hydrogen present in one dozen molecule of hydrogen gas. Convert the given number of hydrogen in terms of number of moles. (b) If hydrogen combines with oxygen in the ratio of 1 : 8 by mass to form water, how many moles of oxygen would be required for the given amount of hydrogen gas? (Atomic mass of H= 1.0 u,0= 16.0 u)  

Answer:

   (a) The number of particles, atoms, molecules or ions present in one mole of any substance is fixed, i.e., and it is called Avogadro's number, m (b) Number of moles of water Number of moles of (c) 1 mol molecules              5.5 moles of molecules molecules 2.2 moles of  molecules moIecules