molecular formula lecture1.notebook
March 07, 2012
Molecular formula­ the actual formula of a compound.
­ has the empirical formula unit repeated once or more then once.
Example: glucose C6H12O6 has an empirical formula of CH2O. We can rewrite the glucose formula as (CH2O)6
When solving problems to figure out the molecular formula we need to calculate how many times the empirical formula mass goes into the molecular formula mass.
Example: A compound with an empirical formula CH2O has a molecular mass of 120.12 g/mol. Find the molecular formula
Mar 6­1:39 PM
Determine the empirical formula of a compound containing 63.50% silver, 8.25% nitrogen and 28.25% Oxygen.
Determine the empirical formula of a compound found to contain 52.11% carbon, 13.14% hydrogen, and 34.75% oxygen.
Mar 6­1:54 PM
A compound is found to have an empirical formula of P2O5 and the molar mass of the compound is 283.9 g/mol
Find the molecular formula of the compound.
Mar 7­11:18 AM
A compound with a formula mass of 42.08 amu is found to contain 85.64% Carbon and 14.36% hydrogen by mass. Find its molecular formula.
Chemical analysis shows that citric acid contains 37.51% C, 4.20% H, and 58.29% O. What is the empirical formula of the compound?
Mar 6­1:55 PM
A neurotransmitter norepinephrine is 56.8%C, 6.5% H, 28.4% O, and 8.3% N. Its molar mass is 169 g/mol. Find the molecular formula of the compound.
A certain sugar has a chemical composition of 40% C, 6.6% H and 53.3% O. The molar mass is 180 g/mol. What is the molecular formula?
Mar 6­2:10 PM
Mar 6­2:15 PM
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