Assertion (A): one atomic mass unit is a mass unit equal to exactly one twelfth the
mass of one atom of carbon – 12.
Reason (R): The mass of 1 mole of a substance is equal to its relative atomic or
molecular mass in gram
Answers
Assertion: One atomic mass unit is defined as one-twelfth of the mass of one carbon-12 atom. Reason: Carbon-12 isotope is the most abundant isotope of carbon and has been chosen as the standard.
Answer:
Hope it helps!
Step-by-step explanation:
Assertion: One atomic mass unit is defined as one-twelfth of the mass of one carbon-12 atom. Reason: Carbon-12 isotope is the most abundant isotope of carbon and has been chosen as the standard. The assertion is true but Reason is false.
If it were 24 g, instead of 12 g, then the weight of 1 mole of substance would equal 2 times the atomic/molecular mass in grams. Since the masses of all elements are defined in terms of amu, which are ultimately based on the mass relative to carbon-12, this ratio holds for all any atom or molecule.
Molar mass is defined as the mass in grams of one mole of a substance. The units of molar mass are grams per mole, abbreviated as g/mol. ); a carbon atom with six proton and six neutrons in its' nucleus, surrounded by six electrons.