(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.


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