Which of the following compounds does not have similarity in their structural aspect?

At $300 \ K$ temperature,$20 \ g \ H_2$,$220 \ g \ CO_2$,and $140 \ g \ N_2$ are filled in a vessel having volume $2 \ L$. Find the total pressure in $bar$ unit and which gas is removed from the vessel so that pressure can be reduced by $50 \%$. $(R = 8.34 \times 10^{-2} \ L \ bar \ K^{-1} \ mol^{-1})$

$1 \ g$ equivalent of a substance is present in:

Blue vitriol is

At $T(K)$,a gaseous mixture contains $H_2$ and $O_2$. The total pressure of the mixture is $2 \ bar$. The partial pressure of $H_2$ is $1.778 \ bar$. What is the weight $(w/w)$ percentage of $H_2$ in the mixture?

An athlete is given $100 \ g$ of glucose $(C_6H_{12}O_6)$ for energy. This is equivalent to $1800 \ kJ$ of energy. The $50 \ \%$ of this energy gained is utilized by the athlete for sports activities at the event. In order to avoid storage of energy,the weight of extra water he would need to perspire is $......... \ g$ (Nearest integer).
Assume that there is no other way of consuming stored energy. Given: The enthalpy of evaporation of water is $45 \ kJ \ mol^{-1}$.
Molar mass of $C, H$ and $O$ are $12, 1$ and $16 \ g \ mol^{-1}$.