CHEMISTRY
JAMB 2023 - Question 2
Chemistry 2023 JAMB Past Questions - Question 2: For the reaction NH4NO2 → N2 + 2H2O, calculate the volume of nitrogen that would be produced at S. T. P from 3.2 g of the dioxonitrate(iii)salt. (Relative atomic masses: N = 14, O = 16, H = 1)
A:
B:
C:
D:
Correct Answer
D
Explanation
To find the volume of nitrogen produced at STP from 3.2 g of NH4NO2, we'll first calculate the number of moles of NH4NO2 using its molar mass, and then use the stoichiometry of the reaction to find the number of moles of nitrogen produced. Finally, we'll use the ideal gas law to find the volume of nitrogen at STP.
- Calculate the molar mass of NH4NO2: NH4NO2 = (1 * 14) + (4 * 1) + (1 * 14) + (2 * 16) = 14 + 4 + 14 + 32 = 64 g/mol
- Calculate the number of moles of NH4NO2: Number of moles = Mass / Molar mass = 3.2 g / 64 g/mol = 0.05 moles
- According to the balanced chemical equation: NH4NO2 → N2 + 2H2O 1 mole of NH4NO2 produces 1 mole of N2.
- Now, we'll use the ideal gas law to find the volume of nitrogen at STP (Standard Temperature and Pressure): At STP, 1 mole of gas occupies 22.4 liters.Volume of N2 = Number of moles * 22.4 liters/mol = 0.05 moles * 22.4 liters/mol = 1.12 liters

