Which of the following statements is/are true regarding composition stoichiometry?
I The mass of 6.022 x 1023 molecules of Na is equal to 23.0 grams.
II Boron has an average atomic mass of 10.81 amu. It has two isotopes, B-10 (10.01
amu) and B-11 (11.01 amu). There is more naturally-occurring B-10 than B-11.
III In N2O4, the mass of the oxygen is twice that of the nitrogen.
IV The compound C6H12O2N has for its simplest formula C3H6ON1/2.
I. Technically I is not true because one mole Na has a mass of 22.989768 g according to my periodic chart. But rounded 23.0 would be OK in most circumstances. So this COULD be true depending upon how many decimals are in the rules of the question.
II. Not true because there is more B-11 than B-10.
III. Not true. There is twice the moles of O vs N but not twice the mass; i.e., 28 g N vs 64 g O which is not a factor of two.
IV. Not true. The simplest formula (the empirical formula) is C6H12O2N.