How many alpha hydrogens (hydrogens on carbon atoms directly attached to the cationic carbon, i.e. hyperconjugating C-H bonds) are present in the 2,3-dimethylbutan-2-yl cation, $(CH X_{3}) X_{2} C X^{+} - CH (CH X_{3}) X_{2}$ ? Give the answer as an integer; do not count the hydrogens on carbons further away.

Numerical answer type, tolerance 0.5.

Answer: 7

The cationic carbon (C2) is attached to two methyl carbons (3 H each) and to the CH carbon (C3, 1 H). Alpha hydrogens

= 3 + 3 + 1 = 7

. The six methyl hydrogens on C3 are beta and are not counted.