Equilibrium and Volume? (1 Viewer)

Lemiixem

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Hey Guys,
I was reading through "Students Guide to HSC Chemistry" when I came across this volume explanation that really confused me.
Under dot point 2.2.4 'Identify factors which can affect the equilibrium in a reversible reaction.'
This is taken directly from"Students Guide to HSC Chemistry":

Volume
Any change in volume in a gaseous equilibrium is simply a change in pressure. As such, treat increases in volume as decreases in pressure, as there are more moles of gas in the fixed space, and treat decreases in volume as increases in pressure.


What I don't understand is how an increase in volume is a decrease in pressure? Shouldn't it be the other way around? An increase in volume is a decrease in pressure?
 

nightweaver066

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An increase in volume essentially means creating more space in that system.

By creating more space, you alleviate the pressure of the gases in the system (decreasing the pressure).
 

clementc

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I like to think of pressure as kind of being how packed and crowded something is and how much people get pressed against the walls.

So if you think of a room with 100 people. If we enlarged the room into something like a auditorium, would the room seem more packed or less packed? Would there be fewer/more people squished against the walls?
Similarly, think of if we herded these people into a tiny cupboard. Would this decrease in volume cause more or less crowding? Would there be more or less people squished into the wall? >=0
 

someth1ng

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What I don't understand is how an increase in volume is a decrease in pressure? Shouldn't it be the other way around? An increase in volume is a decrease in pressure?
Pressure: how many particles you have per volume.
Volume: how much space you have.

For the sake of demonstration:
Pressure=Particles/Volume

.`. if you increase volume then the pressure will decrease.
 

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