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A scientific sampling instrument landed on a comet. Four of the organic compounds detected on the co

Regents Chemistry Exam August 2022


A scientific sampling instrument landed on a comet. Four of the organic compounds detected on the comet are methyl isocyanate, propanone, propanal, and ethanamide. The structural formula for methyl isocyanate is shown below:



76. Identify the element in these four compounds that makes them organic compounds. [1]

Carbon is an element that must be present in all organic compounds

Answer: Carbon

77 Write the names of the two organic compounds detected on the comet that are isomers of each other. [1]


Isomers are two molecules with the same formula but different structure. Propanone and propanal both have three carbons, six hydrogens and one oxygen. Tables P and R can be used to determine the number of carbons and functional group. Propanone is a ketone and propanal is an aldehyde. These two molecules have the same formula, C3H6O but different structure.

Answer: Propanone and propanal

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