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3 years ago

Stoichiometry. Are my answers right?

Chemistry

1 answer:

OverLord2011 [107]3 years ago

6 0

Answer:

Congratulations. Mostly correct.

Step-by-step explanation:

Part I. Gold

Moles of Au = 35.12 2g × 1/196.97 = 0.1783 mol Au

Atoms of Au = 0.1783 × 6.022 × 10²³/1 = 1.074 × 10²³ atoms Au

Part II. Sucrose

Molar mass = 342.30 g/mol

Moles of C₁₂H₂₂O₁₁ = 1.202 g × 1/342.30

Moles of C₁₂H₂₂O₁₁ = 0.003 512 mol C₁₂H₂₂O₁₁

Moles of C = 0.003 512 × 12/1 = 0.042 14 mol C

Moles of H = 0.003 512 × 22/1 = 0.077 25 mol H

Moles of O = 0.003 512 × 11/1 = 0.038 63 mol O

Atoms of C = 0.042 14 × 6.022 × 10²³ = 2.538 × 10²² atoms C

Atoms of H = 0.077 25 × 6.022 × 10²³ = 4.652 × 10²² atoms H

Atoms of O = 0.038 63 × 6.022 × 10²³ = 2.326 × 10²² atoms O

Minor Quibbles:

You put the moles of sucrose in the molar mass slot.

You got the wrong exponents for the atoms of C, H, O.

You followed the rules for significant figures for gold, but not for sucrose.

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3 years ago

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