Chemistry Module 2 - Chapter 3 Flashcards
What is the symbol for amount of substances?
n
What is the unit used to measure amount of substance?
Mole
What does Avogadro’s constant represent?
The number of atoms per mole of the carbon-12 isotope.
What is the value of Avogadro’s constant?
6.02 x 10^23
How do you calculate the mass of 1 mole of the element?
Mass of 1 mole = relative atomic mass in grams
How do you calculate moles when mass and molar mass are given?
Moles (mol) = mass (g) ÷ molar mass (g mol (-1))
State Avogadro’s law.
Under the same temperature and pressure, one mole of any gas would occupy the same volume.
How much volume does a gas occupy, at room temperature and pressure?
24dm^3 or 24000cm^3
Define molar gas volume.
The volume per mole of gas molecules.
Why do different gas particles occupy the same volume?
The gas particles are very spread out, hence individual differences have no effect.
How do you calculate moles when gas volume is given?
Moles (mol) = volume (dm^3) ÷ 24
OR
Moles (mol) = volume (cm^3) ÷ 24000
What are the ideal ways in which gases behave? (5)
- They are in continuous motion.
- No intermolecular forces experienced.
- Exert pressure when they collide with each other or container.
- No kinetic energy is lost in the collisions.
- When temperature increases, kinetic energy of gases also increase.
Write down the ideal gas equation (in words and symbols, including the units)?
pV = nRT
Pressure (Pa) x volume (m^3) = number of moles (mol) x gas constant (8.314 J mol-1) x temperature (K)
One atmospheric pressure is equal to how many pascals?
1 atm = 101325 Pa
0°C is equal to how many kelvin?
273 K