Amount Of Substance

Question 1

Define relative atomic mass (Ar)

Question 2

Define relative molecular mass (Mr)

Question 3

Avogadro’s constant equation

Answer 3

No. Of particles = moles x avogadro’s number (6.02 x10^23)

Question 4

Ideal gas equation (give units)

Answer 4

pV = nRT

p = pressure, Pa
V = volume, m3
n = moles
R = gas constant, JK-1mol-1
T = temperature, K

Question 5

Empirical formula

Answer 5

The simplest whole number ratio of atoms of each element in a compound

Question 6

Molecular formula

Answer 6

The actual number of atoms of each element in a compound

Question 7

Percentage atom economy

Answer 7

( molecular mass of desired product / sum of molecular masses of all reactants ) × 100

Question 8

Economic, ethical & environmental advantages for society and for industry of developing chemical processes with a high atom economy

Answer 8

The higher the % atom economy, the cheaper the process.
Because less time and machinery is needed to separate the desired product from the by-products and waste