Final answer:
The molecular formula for NOCl₂ with a mass of approximately 100.912 g/mol is NOCl₂, corresponding to options a. NOCl₂ and d. Cl₂NO, as they are the same compound with different notation.
Step-by-step explanation:
To find the molecular formula for NOCl₂ with a mass of approximately 100.912 g/mol, we first need to calculate the molar masses of each candidate molecule and then compare them to the given molecular mass. The atomic masses used in the calculations are approximately: N (14.01 amu), O (16.00 amu), Cl (35.45 amu).
For NOCl₂ (a. NOCl₂):
N (14.01) + O (16.00) + 2×Cl (2×35.45) = 14.01 + 16.00 + 70.90 = 100.91 amu
For NO₂Cl (b. NO₂Cl):
N (14.01) + 2×O (2×16.00) + Cl (35.45) = 14.01 + 32.00 + 35.45 = 81.46 amu
For ClNO₂ (c. ClNO₂):
This is simply another way to write NO₂Cl, so the molar mass will be the same: 81.46 amu.
For Cl₂NO (d. Cl₂NO):
2×Cl (2×35.45) + N (14.01) + O (16.00) = 70.90 + 14.01 + 16.00 = 100.91 amu
The correct formula with the approximate molar mass of 100.912 g/mol is NOCl₂, which matches option a. NOCl₂ and option d. Cl₂NO; these two are considered the same compound written differently.