Question

Write molecular formulas for each bicycloalkane, given its number of carbon atoms. (a) Hydrindane ( 9 carbons) (b) Decalin (10 carbons) (c) Norbornane (7 carbons)

Short answer

Answer: The molecular formulas for the bicycloalkanes are as follows: 1. Hydrindane: C_9H_{18} 2. Decalin: C_{10}H_{20} 3. Norbornane: C_{7}H_{14}

Step-by-step solution

(a) Hydrindane)

In case of hydrindane, we have 9 carbon atoms. If it were a linear alkane, we would use the formula CnH(2n+2), which in this case would be C9H20. However, hydrindane has a bicyclic structure with two bridges which removes 2 hydrogen atoms. So, the molecular formula for hydrindane is: C_9H_{18}.

(b) Decalin)

Decalin has 10 carbon atoms. Following the same procedure as above, we will calculate C10H22, which would be the molecular formula for a linear alkane. Considering decalin is a bicyclic structure with two bridges which removes 2 hydrogen atoms, the molecular formula for decalin is: C_{10}H_{20}.

(c) Norbornane)

Norbornane consists of 7 carbon atoms. If it were a linear alkane, we would calculate C7H16 by applying the formula CnH(2n+2). Since norbornane is a bicyclic alkane with two bridges in its structure, we have to remove 2 hydrogen atoms. The final molecular formula for norbornane is: C_{7}H_{14}.