The empirical formula : CH₂O
The molecular formula : C₈H₁₆O₈
the subscripts for C, H, and O : 8,16,8
Further explanation
The empirical formula is the smallest comparison of atoms of compound forming elements.
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
(empirical formula) n = molecular formula
The principle of determining empirical formula and molecular formula
Determine the mass ratio of the constituent elements of the compound. Determine the mole ratio by dividing the elemental mass with the relative atomic mass obtained by the empirical formula Determine molecular formulas by looking for values of n
Percentage of elements A and B in AxBy compounds:
% A in AₓBy = (x x Ar A / Mr AₓBy) x% AₓBy
% B in AₓBy = (y x Ar B / Mr AₓBy) x% AₓBy
It is known about the% mass of each element
The complete question must be :
A Compound Is 40.0 % C, 6.70% H, And 53.3% O By Mass. Assume That We Have A 100g Sample Of This Compound. The Molecular Formula Mass Of This Compound Is 240 Amu. what are the subscripts in the actual molecular formula? enter the subscripts for c, h, and o, respectively, separated by commas (e.g., 5,6,7)
To find the empirical formula, we look for its mole ratio (% mass/ its relative atomic mass)
C = 40 / 12 = 3.3
H = 6.70/ 1 = 6.70
O = 53.3 / 16 = 3.3
To simplify the comparison as an integer, we divide by the mole ratio of the smallest element
C = 3.3/3.3= 1
H = 6.7 /3.3 = 2
O = 3.3/3.3 = 1
So the empirical formula:
CH₂O
We look for the molecular formula to get the number of atoms making up the compound
(CH₂O) n = molecular formula
(1.12 + 2.1 + 16) n = 240
(30) n = 240
n = 8
So molecular formula = C₈H₁₆O₈
Learn more
the molar mass of a substance
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Determine the empirical and molecular formulas
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Determine the molecular formula of the compound
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Keywords: empirical formula, molecular formula, mass, mole