Chapter 3 - Amount of Substance

Question 1

How many particles in a mole?

Answer 1

6.02 x 10^23 (Avogadro constant)
This is the number of particles in 12g of Carbon-12

Question 2

What is molar mass?

Answer 2

Molar mass gives the mass in grams in each mole of the substance

Question 3

What is the equation for moles?

Answer 3

moles (mol) = mass (g) / Molar mass (g/mol)

Question 4

What is an empirical formulae?

Answer 4

It is the simplest whole-number ratio of atoms in a compound.
These are important for giant compounds as the actual formula would be too large

Question 5

What is the equation for moles of gas at RTP?

Answer 5

At 298K and 100kPa
moles (mol) = volume of gas (dm^3) / 24 dm^3

Question 6

What is the ideal gas equation?

Answer 6

pV = nRT
p = pressure (Pa)
V = volume (m^3)
n = moles (mol)
R = ideal gas constant (8.314 J mol^-1 K^-1)
T = temperature (K)

Question 7

Convert cm^3 to m^3

Answer 7

x 10^-6

Question 8

Convert dm^3 to m^3

Answer 8

x 10^-3

Question 9

Convert degrees C to K

Answer 9

+273

Question 10

Convert kPa to Pa

Answer 10

x 10^3

Question 11

Convert 1atm to kPa and Pa

Answer 11

100 kPa or 100000 Pa