A 2.00 g sample of a mixture of $CaCO_3$ and $CaSO_4\cdot2H_2O$ was heated to a constant mass of 1.55 g. What percent by mass of the original sample was $CaCO_3$?

10 g of a mixture of $NaHCO_3$ and $Na_2CO_3$ has 1.68 g of $NaHCO_3$. On heating, if the residue weighs 8.28 g, what is the percentage purity of $Na_2CO_3$ in the mixture?

A 0.518 g sample of lime stone is dissolved in $HCl$ and then the calcium is precipitated as ${\rm{Ca}}{{\rm{C}}_2}{{\rm{O}}_4}$. After filtering and washing the precipitate, it requires 40.0 mL of $0.250N{\rm{KMn}}{{\rm{O}}_4},$, solution acidified with ${{\rm{H}}_2}{\rm{S}}{{\rm{O}}_4}$ to titrate is as, ${\rm{MnO}}_4^ - + {{\rm{H}}^ + } + {{\rm{C}}_2}{\rm{O}}_4^{2 - } o {\rm{M}}{{\rm{n}}^{2 + }} + {\rm{C}}{{\rm{O}}_2} + 2{{\rm{H}}_2}{\rm{O}}$. The percentage of ${\rm{CaO}}$ in the sample is :

From the equation, $3{{\rm{C}}_2}{{\rm{H}}_2} o {{\rm{C}}_6}{{\rm{H}}_6},$ find the volume of acetylene (NTP) for the manufacture of 3 mole of benzene:

How many milligram of iron (${\rm{(F}}{{\rm{e}}^{2 + }})$ are equal to 1 mL of 0.1055 $N{{\rm{K}}_2}{\rm{C}}{{\rm{r}}_2}{{\rm{O}}_7}$equivalent?

How many moles are present in 32g of oxygen gas ($O_2$)? (Atomic mass of O = 16u)

How many milligram of iron (${\rm{(F}}{{\rm{e}}^{2 + }})$ are equal to 1 mL of 0.1055 $N{{\rm{K}}_2}{\rm{C}}{{\rm{r}}_2}{{\rm{O}}_7}$equivalent?

The volume of ${O_2}$ at STP required for the complete combustion of 4g $C{H_4}$ is

20g of hydrogen gas reacts with 40g of oxygen to produce water. Which is the limiting reagent and how much water is formed(in grams)?

How many litre a 0.5 N solution of an oxidising agent are reduced by 2 litre of 2.0 N solution of a reducing agent?

What products are expected from the disproportionation reaction of hypochlorous acid