Question

Calculate the number of moles in the following

(Atomic mass of Fe = 56u, S = 32u, O = 16u)



(a) 98 g of Fe

(b) 18.066 × 1021 atoms of SO2

(c) 12.044 × 1023 atoms of H2O​

Answer 1

Explanation:

$no. \: of \: moles = \frac{given \: mass}{molar \: mass}$

$= \frac{98}{56} = 1.75 \: moles \: of \: iron$

$no. \: of \: moles = \frac{no. \: of \: atoms \times atomicity}{avogadro \: constant}$

$\frac{18.066 \times {10}^{21} \times 3 }{6.022 \times {10}^{23} } = 0.09 \: moles \: of \: sulphur \: oxide$

$\frac{12.044 \times {10}^{23} \times 3 }{6.022 \times {10}^{23} } = 6 \: moles \: of \: water$

Therefore, these are your answers.

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