If a manometer reads #"681.7 torr"#, and the mercury is higher on the left half of the sidearm (where the right side is open to the atmosphere) by #"9.96 cm"#, what is the pressure of the gas inside in #"bars"#?
1 Answer
The idea is that the pressure of the gas in the bulb balances out the pressure of the air (the atmospheric pressure) to some extent.
It is implied that mercury is in the manometer, and the height
Since the manometer reads
#Deltah = "9.96 cm Hg" = "99.6 mm Hg" = "99.6 torr"# ,
it means that there is a difference in pressure of
Since the mercury is higher on the left half of the sidearm, it means the pressure of the gas inside is weaker than the atmospheric pressure.
Therefore,
#color(green)(P_"gas") = "681.7 torr" - "99.6 torr" = color(green)("582.1 torr")#
In
#color(blue)(P_"gas") = 582.1 cancel"torr" xx cancel"1 atm"/(760 cancel"torr") xx (1.01325xx10^5 cancel"Pa")/cancel"1 atm" xx "1 bar"/(10^5 cancel"Pa")#
#=# #color(blue)("0.776 bars")#
CHALLENGE: What would the pressure of the gas inside be in
Answer:
(highlight to see)