Question

A 20 $g$ chunk of dry ice is placed in an empty 0.75 $L$ wire bottle tightly closed what would be the final pressure in the bottle after all $C{O}_2$ has been evaporated and temperature reaches to 25°$C$?

• A. 15.8
• B. 21.2
• C. 12.5
• D. none

Answer 1

Answer: (A)

$w$ = 20 $g$ dry $C{O}_2$

which will evaporate to develop pressure

$m$ = 44, $V$ = 0.75 $L$, $P$ = ?, T = 298 $K$

$PV=\frac{w}{m}RT$ (as $PV=nRT$ & $n=\frac{w}{m}$)

$P\times 0.75=\frac{20}{44}20/4450.0821\times 298$

P = 14.228 $atm$

Pressure inside the bottle = $P$ + $atm$ pressure

$=14.828+1=15.828$ $atm$