If we consider that 1/6, in place of 1/12. Mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of substance will

Explanation

The standard for atomic masses is based on the carbon-12 isotope, where one mole of carbon-12 atoms is assigned a mass of exactly 12 atomic mass units (u). This isotope is assigned a mass of 12 u by definition.The given question proposes considering the mass of a carbon atom to be 1/6 (instead of 1/12) as the relative atomic mass unit. In other words, the mass unit would be 1/6th the mass of a carbon-12 atom.The molar mass of a substance is the mass of one mole of that substance. If the mass unit is changed to 1/6th, the molar mass of any substance (which is expressed in atomic mass units) will increase two-fold because the reference unit is smaller. Therefore, the correct answer is that the mass of one mole of the substance will increase two-fold.