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Calculate the number of C, H, O adams in 9.74 grams of glucose. Be sure your answer has the correct number of significant figures.

User Hasusuf
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1 Answer

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1.Calculating the number of C, H, O atoms in 9.74 grams of glucose.

Given that :

• Mass of C6H12O6 = 9.74g

,

• Molecular mass C6H12O6 =180.156g/mol

,

• Moles of C6H12O6 = mass/M.Mass

=9.74g/180.156g/mol

=0.054moles.

2. Calculate mole ratio of C, H, O , since we have 0.054moles of C6H12O6

(2.1) Carbon → 1 mole C6H12O6 : 6mol C

so, 0.054moles : x mol C

Therefore x mol C = 0.054 * 6 = 0.324moles of Carbon

• Number of atoms for C

No of C atoms = mole* Avogadro number

=0.324 * 6.022*10^23

=1.95x10^23 atoms

(2.2) Hydrogen → 1 mole of C6H12O6 : 12 mol of H

So; 0.054moles : x mol H

Therefore xmol H = 0.054*12 = 0.648 moles of Hydrogen

• Number of atoms for H

No of H atoms = 0.648 * 6.022*10^23

=3.90x10^23 atoms .

(2.3) Oxygen → 1 mole of C6H12O6 : 6 mol of O

So, 0.054 moles : xmol O

Therefore x mol O = 0.054 * 6 =0.324 moles

• Number of atoms for Oxygen =0.324 * 6.022*10^23

=1.95x10^23 atoms

Finally, number of C atoms =1.95x10^23 atoms. number of H atoms =3.90x10^23 atoms . number of O atoms =1.95x10^23 atoms