Answer: Empirical formula is 
Explanation: We are given the masses of elements present in a sample of compound. To evaluate empirical formula, we will be following some steps.
<u>Step 1 :</u> Converting each of the given masses into their moles by dividing them by Molar masses.

Molar mass of Carbon = 12.0 g/mol
Molar mass of Hydrogen = 1.0 g/mol
Molar mass of Oxygen = 16.0 g/mol
Moles of Carbon = 
Moles of Hydrogen = 
Moles of Oxygen = 
<u>Step 2: </u>Dividing each mole value by the smallest number of moles calculated above and rounding it off to the nearest whole number value
Smallest number of moles = 13.76 moles



<u>Step 3:</u> Now, the moles ratio of the elements are represented by the subscripts in the empirical formula
Empirical formula becomes = 
The answers from top to bottom right to left are
3,1,2,4
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Answer:
A. True
Explanation:
Mole is the unit associated with measuring substances in chemistry. Chemicals are usually measured in moles and it is derived from the formula - mass/molar mass.
This makes the mole a definition of the representation of a macroscopic quantity of matter that can be used in the laboratory and hereby validates the answer as being true .