1.2 Flashcards
What are the four variables that describe the physical behavior of gases in a sample?
Pressure (P)
temperature (T)
volume (V)
amount (n)
Define pressure?
results from the number of collisions per unit time on inside walls of container
Express pressure
pressure = force/ area
What are the units for pressure?
Pascals; which are Pa= N/m^2
true or false: a straw sucks the liquid up
false;
sucking a straw decreases the internal pressure of the object, therefore in comparison the Fatm (the atmospheric force or pressure) is higher. Gas flows from high pressure to low pressure; when something is in its path it will push it along
true or false; gas travels from high pressure to low pressure and when there is something in its way it will push it along
true
What does a barometer measure?
measures the total atmospheric pressure
what does a manometer measure?
measures the differences in pressure
Describe how a barometer works?
at 760 mm the column of mercury exerts the same pressure on the mercury surface in the dish as the atmosphere does
PHg= Patm
true or false the air pressure decreases with altitude?
true
(because pressure = force/ area; since the effect of the force of gravity decreases as you get further away from the surface of the earth thus air pressure decreases)
air pressure at sea level (0 C)
- how much atm
- how much mmhg
- how much torr
- how much kPa
1 atm = 760 torr= 760 mmHg= 101.325 kPa
1 atm = ? lb/in^2
14.7 lb/in^2
1 torr = 1 mmHg = ? atm
1/760 atm
state boyle’s law and the conditions
P ~ 1/V
at fixed: amount (n) and temperature (T)
k =PV
why does P~ 1/V?
a decrease in volume of gas particles will result in an increased pressure because gas particles will hit the walls of the container more often
(think of a crushed balloon
state charles law and its conditions
V ~T
at fixed: Pressure (P) and amount (n)
k= V/T
Why does V~T?
to maintain the same amount of collisions (P) per area of high temperature, we need a large volume and vice versa; TO MAINTAIN PRESSURE
what is absolute zero?
0 K = - 273.15 C
state Gay- Lussac’s law and its conditions
P~ T
fixed: Volume(V) and amount (n)
k= P/T
true or false: for every 10m below the surface pressure on lungs increase by 1 atm
true
State Avogadro’s law and conditions
V~ n
at fixed: Temperature (T) and Pressure (P)
k= V/n
Why is V~ n?
Increasing the amount(n) in a container will increase the amount of collisions on the walls of the container thus (P) pressure will increase in the same volume.
However to MAINTAIN ORIGINAL PRESSURE therefore the VOLUME MUST INCREASE, so that the same amount of particles will collide with the inside walls per area originally.
true or false: equal volumes of gases 9at same T and P) contain the SAME NUMBER OF PARTICLES
TRUE
