iran-konkur 2022 Q220

iran-konkur · Other · konkur-riazi_1401_specialized Not Maths
220-- Regarding the following, how many statements are correct? $(\mathrm{H=1,\ C=12\ ;\ g.mol^{-1}})$
  • 73.5\% of the molecular mass of paraxylene is contributed by carbon.
  • The number of carbon atoms in a molecule of paraxylene equals the number of styrene molecules.
  • Acetic acid can be obtained directly from a suitable reaction of ethane.
  • Methanol can be obtained by reacting $\mathrm{H_2}$ gas with $\mathrm{CO}$ gas using a suitable catalyst and at a suitable temperature.
  • The monomers forming a polymer with the structural formula [Figure: polymer structural formula showing repeating ester-linked units with carbonyl groups] are one difunctional alcohol and one difunctional acid.

(1) five (2) four (3) three (4) two
[Space for calculations]
\textbf{220--} Regarding the following, how many statements are correct? $(\mathrm{H=1,\ C=12\ ;\ g.mol^{-1}})$

\begin{itemize}
    \item 73.5\% of the molecular mass of paraxylene is contributed by carbon.
    \item The number of carbon atoms in a molecule of paraxylene equals the number of styrene molecules.
    \item Acetic acid can be obtained directly from a suitable reaction of ethane.
    \item Methanol can be obtained by reacting $\mathrm{H_2}$ gas with $\mathrm{CO}$ gas using a suitable catalyst and at a suitable temperature.
    \item The monomers forming a polymer with the structural formula \textit{[Figure: polymer structural formula showing repeating ester-linked units with carbonyl groups]} are one difunctional alcohol and one difunctional acid.
\end{itemize}

(1) five \hfill (2) four \hfill (3) three \hfill (4) two

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\textit{[Space for calculations]}
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