The molar mass of $CaCO_{3}$ is $100 \ g/mol$. The maximum amount of carbon dioxide that can be liberated on heating $25 \ g$ of $CaCO_{3}$ is $.... \ g$.

The number of molecules of $CO_2$ liberated by the complete combustion of $0.1 \ mol$ of graphite in air is

Complete combustion of $3 \ g$ of ethane gives $x \times 10^{22}$ molecules of water. The value of $x$ is ......... (Round off to the Nearest Integer). [Use: $N_{A} = 6.023 \times 10^{23} ;$ Atomic masses in $u$ $C = 12.0, O = 16.0, H = 1.0$]

If $0.5 \ g$ of a mixture of two metals $A$ and $B$ with respective equivalent weights $12$ and $9$ displace $560 \ mL$ of $H_2$ at $STP$ from an acid,the composition of the mixture is:

$5 \ mL$ of $N \ HCl$,$20 \ mL$ of $N/2 \ H_2SO_4$,and $30 \ mL$ of $N/3 \ HNO_3$ are mixed together and the volume is made up to $1 \ L$. The normality of the resulting solution is:

At sea level,the dry air mass percentage composition is given as nitrogen gas: $70.0$,oxygen gas: $27.0$,and argon gas: $3.0$. If the total pressure is $1.15 \ atm$,calculate the ratio of the following respectively:
$(i)$ partial pressure of nitrogen gas to partial pressure of oxygen gas
$(ii)$ partial pressure of oxygen gas to partial pressure of argon gas
(Given: Molar mass of $N_2$,$O_2$,and $Ar$ are $28, 32$,and $40 \ g \ mol^{-1}$ respectively)