NY Regents Chemistry Exam June 2022
The incomplete equation below represents a reaction between 2-butene and hydrogen in the presence of a catalyst, producing one compound, X.
59 Explain, in terms of molecular formulas and structural formulas, why 1-butene is an isomer of 2-butene. 
Explanation: Isomers are molecules with the same molecular formula but different structure.
Answer: 1-butene is an isomer of 2-butene because both compounds have the same molecular formula but different structure (double bond location is different).
60 Draw a structural formula for the missing product, X, in the equation. 
Explanation: This is an organic reaction called addition. In this reaction an alkene (molecule that has C=C) reacts with X2 (where X could be H, Cl, F or I). Double bond turns into single bond and two X's get added (in this case two hydrogens), one on each carbon that used to hold the double bond.
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