Question

A flask of gaseous $CC{l}_4$ was weighed at measured temperature and pressure. The flask was then flushed and filled with $O_2$ at the same temperature and pressure. The weight of the $CC{l}_4$ vapour will be:

• A. five time as heavy as $O_2$
• B. one fifth heavy as compared to $O_2$
• C. same as that of $O_2$
• D. twice as heavy as the $O_2$

Answer 1

Answer: (A)

five time as heavy as $O_2$

Let V be the volume of flask

Since, the pressure and temperature are also same for both the gases, we will have same number of moles for each of them. Therefore, the ratio of weight will be the ratio of molecular weight of the gases.

Molecular weight of $CC{l}_4=154g$
Molecular weight of $O_2=32g$

Hence, the ratio comes out to be nearly 5.