Question

Mass of 0.5 moles of alominium oxide

Answer 1

Number of moles of alominium oxide( Al₂O₃ )= 0.5

Atomic mass of Aluminium = 27 u

Atomic mass of oxygen = 16 u

Molar mass of Al₂O₃ = (2×27)+(3×16)

=(2×27)+(3×16)

= 54+48

= 102 g/mol

We know that :-

$\boxed{ {\boxed{ \tt\large mass = n \times molar \: mass}}} \\ \\ \sf \: where \: n \: is \: number \: of \: moles$

➝ mass of Al₂O₃ = 0.5 × 102

➝ mass of Al₂O₃ =( 5/10) × 102

➝ mass of Al₂O₃ =( 1/2) × 102

➝ mass of Al₂O₃ = 51 g

Answer :

Mass of 0.5 moles of alominium oxide = 51 grams

Additional Information :

$\rm Mass \: percentage = \dfrac{Mass \: of \: Solute}{Mass \: of \: Solution} \times 100 \:$

$\rm Mass \: percentage \:of \: solute= \dfrac{Mass \: of \: Solute}{Mass \: of \: Solution} \times 100 \:$

$\rm n = \dfrac{number \: of \: atoms}{N_A} \\ \\ \sf where : N_A = 6.022 \times {10}^{23} and \: n \: is \: number \: of \: moles$

Answer 2

Given -

${\bullet}$ Number of moles of alluminium oxide = 0.5

We know that -

${\bullet}$ Chemical formula of alluminium oxide = Al₂O₃

${\bullet}$ Atomic mass of oxygen = 16u

${\bullet}$ Atomic mass of alluminium = 27u

${\bullet}$ Molar mass of alluminium

➨ (2 × 27) + (3 × 16)

➨ 54 + 48

➨ 102 g/mol

We also know that -

$\; \; \; \;{\large{\boxed{\bold{\rm{Mass = \: number \: of \: moles \times \: molar \: mass}}}}}$

~ Putting the values

➨ Mass = 0.5 × 102

➨ Mass = (5/10) × 102

➨ Mass = (1/2) × 102

➨ Mass = 1 × 51

➨ Mass = 51 grams

Solution -

Mass of 0.5 moles of alominium oxide is 51 grams.