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Flashcards in Gases Deck (16):
1

Define KMT

Kinetic Molecular Theory
attempts to explain the behaviour of particles in all 3 states of matter

2

Name the 6 principal assumptions of the KMT

-gas consists of tiny particles
-the volume occupied y gas is consist mostly of empty space
-gas particles have no attraction for one another
-gas particles move in straight lines in one direction
-no energy is lost in a collision of gas particles with themselves and the wall of the containers (elastic)
-average kinetic energy for particles is the same for all gases at the same temperature

3

Describe the barometer

-invented by Torricelli
-consist of a dish of mercury and a tube of mercury
-amount of mercury remaining in the tube is controlled by the amount of atmospheric pressure acting on the surface of the mercury in the dish

4

Charles' Law

-states that at a constant pressure the volume of a gasis directly proportional to the kelvin temp.
-studies have shown that is a gas is raised from 0 degrees Celsius to 273 degrees Celsius, its volume doubles
-V1/T1 = V2/T2

5

Gas Laws- Boyle's Law

this law states that at constant temp. the volume of a gas is inversely proportional to the pressure
P1V1 = P2V2

6

Concept of an Ideal Gas

-any gas that obeys all aspects of the KMT
-in reality, there is no such thing, we have real gases however, under certain conditions (low pressure and high temp.) , a real gas could closely approximate an ideal gas

7

Ideal gas equation

PV = nRT
P- pressure
V- volume
n- moles
R- universal gas constant (0.0821 L atm / mol K) or (8.31 L kPa / mol K)
T- temp.

8

Describe Dalton's Law on Partial Pressure

-this law states that in a mixture on gases, each gas exerts a pressure as though it was the only gas in the container. The total pressure for the mixture is the sum of the individual partial pressure
P= nRT/V for each gas then add
OR Ptotal= ntotal RT / V

9

What are the colligative properties

1) vapour pressure- pressure exerted by a vapour in equilibrium with its liquid
2) boiling point- temperature at which vapour pressure is equal to atm
3) freezing point- temperature at which vapour pressure of a liquid is equal to the vapour pressure of a solid
4) osmotic pressure- the pressure required to stop osmosis

10

Describe osmosis

-movement of a solution from a region of high pressure to a region of low pressure
-OP (pi) = M R T i

11

Define a solution

a homogeneous mixture of two or more pure substances
-made up of a solute and a solvent

12

Describe solute and solvent

solute is the substance being dissolved or diluted and the solvent in the one that's doing the dissolving

13

What is the tyndall effect

-a method used to determine if a mixture is a solution or not. By passing a light through the mixture, its a solution if the beam goes straight through, and its not a solution if the beam is scattered

14

Name the qualitative categories

dilute solution- has lots of solvent and very little solute
concentrated solution- has lots of solute very little solvent
unsaturated solution- has less than the maximum amount of solute dissolved in a given quantity of solvent at a specific temp.
saturated solution- has the maximum amount of solute dissolve in a given quantity of solvent at a specific temp.
super saturated solution- has more than the maximum amount of solute in a given quantity of solvent at a specific temp.

15

Define and Name the quantitative terms

these give an exact numeric value for the concentration
morality
molality
% by mass
% by volume
parts per million (ppm)
parts per billion (ppb)
density

16

Desc. Molarity

the abbreviation is molar
the symbol is "M"
by definition molarity refers to the moles of solute per dm^3