A mixture of $CaCO_3$ and $MgCO_3$ weighing 1.84 g on heating leaves a residue weighing 0.96 g. If the percentage by mass of $CaCO_3$ in the original mixture is x%, what is the value of x/2?

If 50.0 g of an impure sample of limestone (calcium carbonate) is heated, it decomposes to produce 14.0 g of calcium oxide and carbon dioxide. Determine the percentage of calcium carbonate in the limestone sample. (Atomic weight: $Ca = 40$)

Number of moles of $N{a_2}S{O_4}$ produced from 1 mole of NaOH

A sample of hydrated copper sulfate (CuSO₄ ⋅ xH₂O) contains 0.25 moles of water. If the total mass of the hydrated salt is 62.5 g, and the anhydrous copper sulfate (CuSO₄) has a molar mass of 160 g/mol, what is the value of 'x' (the number of water molecules per formula unit)?

The number of moles of hydrogen molecules required to produce 20 moles of ammonia through Haber’s process is:

Upon heating, 15.0 g of impure zinc carbonate decomposes completely to produce zinc oxide and carbon dioxide. If 5.6 g of zinc oxide is formed, calculate the percentage purity of the zinc carbonate sample. (Atomic weight: $Zn = 65.4$)

How many moles of water are present in 22.4 L of water vapor at Standard Temperature and Pressure (STP)?

Two elements, R and S, combine to form $RS_2$ and $R_2S_3$. If 10 g of $RS_2$ contains 0.1 mole and 9 g of $R_2S_3$ contains 0.05 mole, find the atomic weights of R and S.

The production of 10 moles of ammonia by the Haber process requires how many moles of hydrogen gas, assuming complete reaction?

What mass of AgCl is precipitated when 25 mL of a 8.45% $\AgNO_3$ solution is mixed with 50 mL of a 5.8% NaCl solution?

Elements X and Y form compounds $XY_2$ and $X_3Y_2$. If 20 g of $XY_2$ contains 0.2 moles and 18 g of $X_3Y_2$ contains 0.1 moles. What are the atomic weights of elements X and Y?