When $0.0168 \, mol$ of $O_2$ obtained from the decomposition of $KClO_3$ is collected over water at $25 \, ^\circ C$,the volume is $428 \, mL$ and the pressure is $754 \, mm$. What is the water vapor pressure at $25 \, ^\circ C$ in $mm$?

$A$ mixture of equal masses of $SO_2$,$CH_4$,and $O_2$ is taken in an empty container at $298 \, K$. If the total pressure is $2.1 \, atm$,the partial pressure of $CH_4$ in the mixture will be .......... $atm$.

Solid $CO_2$ is known as dry ice,because

Fill in the blanks:
$(1)$ Gases like $CO_2$ and $CH_4$ show ............ deviation from ideal gas behavior.
$(2)$ The temperature at which a real gas obeys ideal gas laws over an appreciable range of pressure is called ............ .
$(3)$ The maximum temperature below which a gas can be liquefied is called ............ .
$(4)$ The unit of coefficient of viscosity in the $CGS$ system is ............ .

Assertion: Use of pressure cooker reduces cooking time.
Reason: At higher pressure,cooking occurs faster.

Three layers of liquid are flowing over a fixed solid surface as shown below. The correct order of velocity of the liquid in these layers is: