The number of carbocations from the following that are not stabilized by hyperconjugation is $...........$ .

Rank the transition states that occur during the following reaction steps in order of increasing stability (least $\to$ most stable):
$1.$ $CH_3-O^+H_2 \to CH_3^+ + H_2O$
$2.$ $(CH_3)_3C-O^+H_2 \to (CH_3)_3C^+ + H_2O$
$3.$ $(CH_3)_2CH-O^+H_2 \to (CH_3)_2CH^+ + H_2O$

$A$ certain reaction occurs in two steps as:
$(i)$ $2 SO_{2(g)} + 2 NO_{2(g)} \rightarrow 2 SO_{3(g)} + 2 NO_{(g)}$
$(ii)$ $2 NO_{(g)} + O_{2(g)} \rightarrow 2 NO_{2(g)}$
In the reaction,

Provide four formulas of carbocations.

Which of the following is the most stable carbocation?

The orbital picture of a triplet carbene can be drawn as