iran-konkur 2022 Q207

iran-konkur · Other · konkur-riazi_1401_specialized Not Maths
207-- Considering the structure of the caffeine molecule shown in the figure below, how many of the following statements are correct? ($\text{H}=1,\ \text{C}=12,\ \text{N}=14,\ \text{O}=16\ :\ \text{g.mol}^{-1}$)
[Figure: Structural formula of caffeine molecule showing a bicyclic ring system with $\text{CH}_3$ groups, nitrogen atoms, a carbonyl group, and $\text{CH}_3$ substituents]
  • $0.2$ mol of it has a mass of $39.2$ grams.
  • It has three amide groups and three amine groups.
  • The difference in the number of $\text{C}-\text{H}$ bonds and $\text{C}-\text{N}$ bonds in its molecule is 2.
  • The ratio of the lone pair electrons of the bonds to the number of non-bonding electron pairs in it is $3.75$.

(1) one (2) two (3) three (4) four
\textbf{207--} Considering the structure of the caffeine molecule shown in the figure below, how many of the following statements are correct? ($\text{H}=1,\ \text{C}=12,\ \text{N}=14,\ \text{O}=16\ :\ \text{g.mol}^{-1}$)

\begin{center}
\textit{[Figure: Structural formula of caffeine molecule showing a bicyclic ring system with $\text{CH}_3$ groups, nitrogen atoms, a carbonyl group, and $\text{CH}_3$ substituents]}
\end{center}

\begin{itemize}
    \item $0.2$ mol of it has a mass of $39.2$ grams.
    \item It has three amide groups and three amine groups.
    \item The difference in the number of $\text{C}-\text{H}$ bonds and $\text{C}-\text{N}$ bonds in its molecule is 2.
    \item The ratio of the lone pair electrons of the bonds to the number of non-bonding electron pairs in it is $3.75$.
\end{itemize}

(1) one \quad (2) two \quad (3) three \quad (4) four