Stoichiometry

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Dhamnekar Winod
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Stoichiometry

Post by Dhamnekar Winod »

The alkaloid strychnine, a compound containing carbon, hydrogen, nitrogen and oxygen was submitted for elemental analysis. Combustion of a 0.3432-g sample in oxygen gave 0.2032-g H2O and 0.9483-g CO2.
A 0.4932-g sample yielded 36.5 ml of nitrogen gas with a density of 1.13 g/L. The molecular weight of the compound was found to be 334.

Calculate (a) the percentage composition

(b) the empirical formula

(c) the molecular formula

Any chemistry help will be accepted. I am working on this question.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
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ChenBeier
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Re: Stoichiometry

Post by ChenBeier »

For a) calculate the amount H and C from the given masses either in mol and g and the percentage.
From the second Experiment also calculate the amount of nitrogen N .
b) 100 - the summery of C H N gives the amount of Oxygen O.
c) From the given molar mass and the calculated empiric formula the composition can be calculated.
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Dhamnekar Winod
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Re: Stoichiometry

Post by Dhamnekar Winod »

a) Percentage composition of the compound:
Carbon:75.41%
Nitrogen:8.36%
Hydrogen:6.62%
Oxygen:9.61%

b) C21H22N2O2
c)C21H22N2O2
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
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ChenBeier
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Re: Stoichiometry

Post by ChenBeier »

Calculation path is missing.
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