1) Compounds Y and Z both have the formula C9H18. Both Y and Z react with one molar equivalent of hydrogen in the presence of a palladium catalyst to form 2-methyloctane.
The heat of hydrogenation of Y is less than that of Z.
Y and Z each undergo hydroboration/oxidation to give a primary alcohol (OH attached to a primary carbon).
What is the structure of Y?
2) Compound X has the formula C8H12.
X reacts with two molar equivalents of hydrogen in the presence of a palladium catalyst to form cyclooctane.
Treatment of X with ozone followed by zinc in aqueous acid gives two molar equivalents of the same dialdehyde.
What is the structure of X

See explanation and images attached

Explanation:

We know that the cis isomer has more heat of hydrogenation since it is less stable than the trans isomer. Since the hydrogenation of both compounds yields the same product and the hydroboration/oxidation both give a primary alcohol, they are geometric isomers and Y is the trans isomer (Image 2).

For the compound C8H12, the compound in question must be 1,5- cyclooctadiene since two moles of the same aldehyde was obtained after ozonolysis and reaction with two equivalents of hydrogen gives cyclooctane (Image 1).

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in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.