$300 \ mL$ of a gaseous hydrocarbon when burnt in excess of $O_2$ gave $2.4 \ L$ of $CO_2$ and $2.7 \ L$ of water vapour under same conditions. The molecular formula of the hydrocarbon is:

Diatoms,microscopic organisms,are an abundant food source in the oceans producing carbohydrates from carbon dioxide and water by photosynthesis.
$6CO_2 + 6H_2O + \text{solar energy} \to C_6H_{12}O_6 + 6O_2$
$A$ blue whale gains $75 kg$ of mass per day by feeding on krill. The whale must consume ten times this mass of krill each day. The krill must consume $10.0 kg$ of diatoms to produce $1.0 kg$ of krill. Assuming that the mass gain of a whale's life is due to the consumption of carbohydrates $(C_6H_{12}O_6)$,calculate the moles of $CO_2$ that must be used by the diatoms to produce the carbohydrates consumed by a blue whale in a day.

Volume of $\frac{N}{10}$ $H_2SO_4$ required to neutralize $10 \ mL$ of $5 \ N$ $Na_2CO_3$ is.....$mL$.

$1 \ L$ of $N_2$ and $\frac{7}{8} \ L$ of $O_2$ gases are mixed at the same temperature and pressure. What is the relationship between their masses in the mixture?

If $25 \ mL$ of a $H_2SO_4$ solution is neutralized by $32.63 \ mL$ of $0.164 \ M \ NaOH$ solution,what is the molarity of the $H_2SO_4$ solution (in $M$)?

In the reaction shown,$5 \ g$ of toluene is converted into benzaldehyde with $92 \%$ yield. The amount of benzaldehyde produced is $.... \times 10^{-2} \ g$. (Nearest integer)