$1 \ g$ of a carbonate $(M_2CO_3)$ on treatment with excess $HCl$ produces $0.01 \ mol$ of $CO_2$. The molar mass of $M_2CO_3$ is $.......... \ g \ mol^{-1}$. (Nearest integer)

If equal masses of methane $(CH_4)$ and hydrogen $(H_2)$ are mixed in an empty container at $25\,^oC$,what is the fraction of the total pressure exerted by hydrogen?

$250 \ mL$ of a sodium carbonate solution contains $2.65 \ g$ of $Na_2CO_3$. If $10 \ mL$ of this solution is diluted to $1 \ L$, what is the concentration of the resultant solution (in $M$)?

What is the mass of $33.6 \ dm^3$ of methane gas at $S.T.P.$?

$A$ bottle of cold drink contains $200 \ mL$ liquid in which $CO_2$ is $0.1 \ M$. Suppose $CO_2$ behaves like an ideal gas,the volume of the dissolved $CO_2$ at $STP$ is (in $L$)

Gastric juice contains about $3.0 \ g$ of $HCl$ per liter. If a person produces about $2.6 \ liters$ of gastric juice per day,find the number of antacid tablets required to neutralize all the $HCl$ produced. Consider each antacid tablet contains $400 \ mg$ of $Al(OH)_3$. [Given,atomic masses: $Al=27, O=16, H=1, Cl=35.5$]