1. Stoichiometric Relationships Flashcards
Proximity of particles
Solids, liquids, gases
Close together
Slightly further apart
Far apart
Energy of particles
Solids, liquids, gases
Lower energy
Larger energy
Most energy
Movement of particles
Solids, liquids, gases
Vibrate and rotate in fixed positions
Move about quite freely while in close proximity
Rapid, random movement
Forces of attraction between particles
Solids, liquids, gases
Strong
Moderate
Small
Volume of one mole of gas at STP
22.7 mol dm-3
Volume of one mole of gas at SATP
24.8 mol dm-3
What is the law of conservation of mass?
During any chemical change, the total mass of the products remains equal to the total mass of the reactants
What is the law of constant composition?
A chemical compound always contains the same elements in the same proportion by mass
How is ppm calculated?
mg/dm^3
Why is a primary standard chosen?
Because it has high purity and stability, allowing the substance to be accurately weighed, such that an accurately known concentration can be used reliably for the calibration of other standards
What is a standard solution?
A solution with a known concentration
Assumptions of ideal gases [3]
Negligible volume
Negligible attractive forces
Elastic collisions, no loss of KE
When does a real gas behave like an ideal gas?
High temperatures, low pressures
What remains the same in the Maxwell-Boltzmann speed distribution? [2]
Distribution of speeds
Average KE of gas particles
What changes in the Maxwell-Boltzmann speed distribution?
Individual molecular speeds
Assumptions of Kinetic-Molecular Theory [5]
- Negligible volume
- Negligible FOA
- Continual & random motion
- Perfectly elastic collisions
- KE directly proportional to T
What does the area under the curve for the Maxwell-Boltzmann Speed Distribution represent?
Total no. of molecules with full range of possible speeds
What happens to the curve as temperature increases?
Area under curve remains constant
Curve shifts to the right cos of higher average energy
Flatter distribution since more are moving at higher speeds
If everything remains constant but the type of gas, what will affect the speed of the molecules?
The mass of the molecules or atoms.
Lighter gases will move, on average, faster than heavier gases