Universal gas constant

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The universal gas constant is also called molar constant. It is generally denoted as Ru. It is the product of a gas constant and the molecular mass of the gas. 

 Ru = R M 

 Where R = Gas constant

M = Molecular mass of gas expressed in kg mol

 In general, we take the different molecular mass of the different gas such as M1, M2, M3 and R1, R2, R3 are their gas constant respectively. So, we conclude that 

 M1 R1 = M2 R2 = M3 R3

 Important Notes: 

  1. The value of Ru is same for all the gas. 
  2. SI Unit of Ru is 8314 J / kg mol K or 8.314 kJ / kg mol K 

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