(a) Calculate the number of moles in 112 g of iron.
(b) Calculate the mass of 0.5 mole of sugar (C12H22O11).
[Atomic mass of Fe = 56 u, C = 12 u, H = 1 u, O = 16 u]
(a) Given mass: 112g
Molar mass of iron (Fe) = 56 g/mol
To calculate the number of moles, we will apply the formula given below:
Number of moles = 2
Thus, the number of moles in 112 g of iron is 2
(b) Given: Number of moles = 0.5
Molar mass of C12H22O11 = 12 × atomic mass of C + 22 × atomic mass of H + 11 × atomic mass of O
= 12 × 12 + 22 × 1 u + 11 × 16 u = 342 u or 342 g/mol
Now, to calculate mass, apply the formula:
We can write:
Mass(m) = Number of moles (n) × Molar mass of C12H22O11 (M)
Mass = 0.5 mol × 342g/mol
Mass = 171g
Thus, the mass of 0.5 mole of sugar (C12H22O11) is 171g.