JAMB - Chemistry (2005 - No. 15)
How many hydrogen atoms does a single ring cycloalkane have less than the corresponding open-chain alkane?
Two
Three
Four
One
Selitys
Let's consider an example:
Cycloalkane → Cyclopropane has the formula CH\(_2\)-CH\(_2\)-CH\(_2\) (when drawn in a cyclic form) = C\(_3\)H\(_6\)
Open chain alkane → Propane has the formula CH\(_3\)CH\(_2\)CH\(_3\) (when drawn on a straight chain) = C\(_3\)H\(_8\)
Comparing the two formulas; C\(_3\)H\(_6\) and C\(_3\)H\(_8\), the difference in the hydrogen atoms is two.