Which of the following contains the largest number of ATOMS at room temperature and pressure?
[ Relative atomic masses: H = 1.0, N = 14.0, Cl = 35.5; molar volume of gas at room temperature and pressure = 24dm^3]
A. 2 mol of ammonium gas
B. 3 mol of nitrogen gas
C. 7g of hydrogen gas
D. 90dm^3 of hydrogen chloride gas
Ans: A. Why?