(white Powder) : 42.2% carbon, 6.4% Hydrogen, and 51.4% Oxygen Formula Mass = 342.2965 amu
Molecular Formula:
Empirical Formula:
Identity?what does the drug do?
Here is a sample solved problem: Go thru it.
https://www.jiskha.com/display.cgi?id=1161205566
Emily, you need to learn how to spell chemistry correctly.
To determine the molecular and empirical formulas for the given compound, we need to find the ratio of the elements present in the compound.
1. Start with the percentages of each element:
- Carbon (C): 42.2%
- Hydrogen (H): 6.4%
- Oxygen (O): 51.4%
2. Convert the percentages to grams:
- Assume you have 100g of the compound, so you have:
C: 42.2g
H: 6.4g
O: 51.4g
3. Convert the grams to moles using the atomic masses:
- Carbon (C): atomic mass = 12.01 g/mol
moles of C = mass of C / atomic mass of C
= 42.2g / 12.01 g/mol
≈ 3.516 moles
- Hydrogen (H): atomic mass = 1.01 g/mol
moles of H = mass of H / atomic mass of H
= 6.4g / 1.01 g/mol
≈ 6.34 moles
- Oxygen (O): atomic mass = 16.00 g/mol
moles of O = mass of O / atomic mass of O
= 51.4g / 16.00 g/mol
≈ 3.213 moles
4. Divide the number of moles of each element by the smallest number of moles to obtain the empirical formula:
- Divide the moles of each element by 3.213 (the smallest number of moles):
C: 3.516 / 3.213 ≈ 1.093
H: 6.34 / 3.213 ≈ 1.971
O: 3.213 / 3.213 = 1
- Round off the obtained ratios to the nearest whole number to get the empirical formula:
C: ≈ 1
H: ≈ 2
O: 1
So, the empirical formula is C1H2O1, which can be simplified as CH2O.
To find the molecular formula, we need the formula mass:
Given formula mass = 342.2965 amu
To determine the number of empirical units (n) in the formula mass, divide the formula mass by the empirical formula mass:
n = formula mass / empirical formula mass
n = 342.2965 amu / (12.01 amu + 2.02 amu + 16.00 amu)
n ≈ 22.65
Multiply the subscripts of the empirical formula by n to obtain the molecular formula:
Molecular formula = (CH2O)n = (CH2O)22.65
Since molecular formulas usually consist of whole numbers, the molecular formula would be rounded to the nearest whole number if necessary.
To determine the identity of the drug, you would need additional information such as the common names, chemical names, or structural formulas of drugs with similar empirical and molecular formulas.