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What is the empirical formula of a molecule containing 65.5% carbon 5.5% hydrogen and 29% oxygen?

2 Answers

5 votes
I assume C₃H₃O.

Hope I helped! Tell me if I'm wrong!
User Lohith Korupolu
by
8.2k points
1 vote

Answer: The empirical formula is
C_(3)H_(3)O_1

Step-by-step explanation:

If percentage are given then we are taking total mass is 100 grams.

So, the mass of each element is equal to the percentage given.

Mass of C = 65.5 g

Mass of H = 5.5 g

Mass of O = 29.0 g

Step 1 : convert given masses into moles.

Moles of C =
\frac{\text{ given mass of C}}{\text{ molar mass of C}}= (65.5g)/(12g/mole)=5.5moles

Moles of H =
\frac{\text{ given mass of H}}{\text{ molar mass of H}}= (5.5g)/(1g/mole)=5.5moles

Moles of O =
\frac{\text{ given mass of O}}{\text{ molar mass of O}}= (29g)/(16g/mole)=1.8moles\approx 1moles

Step 2 : For the mole ratio, divide each value of moles by the smallest number of moles calculated.

For C =
(5.5)/(1.8)=3

For H =
(5.5)/(1.8)=3

For O =
(1.8)/(1.8)=1

The ratio of C : H : O= 3: 3: 1

Hence the empirical formula is
C_(3)H_(3)O_1

User Paquita
by
7.1k points