<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
0.340 mol Br2 ( </span>6.022 x 10^23 molecules / mol ) = 2.05 x 10^23 molecules
Number 2 is the correct answer
The empirical formula for this vitamin : C₃H₄O₃
<h3>Further explanation
</h3>
The empirical formula is the smallest comparison of atoms of compound =mole ratio of the components
The principle of determining empirical formula
- Determine the mass ratio of the constituent elements of the compound.
- Determine the mole ratio by dividing the percentage by the atomic mass
Mass of C in CO₂ :(MW C = 12 g/mol, CO₂=44 g/mol)

Mass of H in H₂O :(MW H = 1 g/mol, H₂O = 18 g/mol)

Mass O = Mass sample - (mass C + mass H) :

mol ratio C : H : O =

Explanation:
Percentage composition of oxygen = (80/134) * 100% = 59.7%.
Answer:
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