Question

The molar mass of NI₃ is 394.71 g/mol. how many moles of I₂ will form 3.58 g of NI₃?

A. 0.00907 moles
B. 0.00940 moles
C. 0.0136 moles
D. 0.0212 moles

Answer 1

The correct answer is C. 0.0136 moles of I2, which is calculated by first determining the moles of NI3 using its molar mass of 394.71 g/mol, then applying the stoichiometry of the reaction.

Step-by-step explanation:

To determine how many moles of iodine, I2, will form from 3.58 g of NI3, we need to first calculate the moles of NI3 using its molar mass. A two-step calculation is required:

1. Calculate the moles of NI3 from the mass given using its molar mass.
2. Use the stoichiometry of the reaction to find the moles of I2 produced from the moles of NI3.

To convert from grams to moles of NI3, we use the formula:

moles of NI3 = mass (g) / molar mass (g/mol)

For NI3 with a molar mass of 394.71 g/mol, the calculation is:

moles of NI3 = 3.58 g / 394.71 g/mol = 0.00907 moles

The reaction of NI3 forming I2 would typically follow the stoichiometry of:

2 NI3 → N2 + 3 I2

For every 2 moles of NI3, 3 moles of I2 are produced. So, we calculate the moles of I2 formed as follows:

Moles of I2 = (3/2) * moles of NI3 = (3/2) * 0.00907 moles = 0.0136 moles

Therefore, the correct answer is C. 0.0136 moles of I2.