A pre-weighed vessel was filled with oxygen at NTP and weighed. It was then evacuated, filled with a — States of Matter and Gaseous State Chemistry Question

💡 Solution & Explanation

Under the same conditions of temperature and pressure, equal volumes of gases contain the same number of moles (Avogadro's law). n($O_2$) = n($SO_2$) => m($O_2$)/M($O_2$) = m($SO_2$)/M($SO_2$) => m($O_2$)/32 = m($SO_2$)/64 => m($O_2$) = 0.5 * m($SO_2$). Hence, the mass of oxygen is half that of $SO_2$.