The set of numerical coefficients that balances the equation $K_2CrO_4 + HCl \to K_2Cr_2O_7 + KCl + H_2O$ is

In the reaction: $4A + 2B + 3C \to A_4B_2C_3,$ what will be the number of moles of product formed,starting from $1 \, mole$ of $A, 0.6 \, mole$ of $B$ and $0.72 \, mole$ of $C$?

$CaCO_3 + 2HCl \to CaCl_2 + CO_2 + H_2O$ ; In this chemical reaction,what will be the amount of calcium chloride formed when $10 \ g$ of calcium carbonate and $400 \ mL$ of $0.25 \ M$ $HCl$ are used? (Atomic masses: $Ca=40, C=12, O=16, H=1, Cl=35.5$)

Phosphoric acid is prepared commercially from phosphate ore as follows:
$Ca_3(PO_4)_2 + 3SiO_2 + 5C + 5O_2 + 3H_2O \to 3CaSiO_3 + 5CO_2 + 2H_3PO_4$
If $1.0 \ kg$ each of calcium phosphate and silica are used with an excess of $C$,$O_2$,and $H_2O$,what is the maximum quantity of phosphoric acid that can be produced (in $kg$)? (Atomic masses: $Ca = 40, P = 31, Si = 28, O = 16, H = 1$)

Assign $A, B, C, D$ from the given type of reaction.
$NaBr + AgNO_3 \longrightarrow AgBr \downarrow + NaNO_3$

$A$ mixture of $100 \ mmol$ of $Ca(OH)_2$ and $2 \ g$ of $Na_2SO_4$ was dissolved in water and the volume was made up to $100 \ mL$. The mass of $CaSO_4$ formed and the concentration of $OH^{-}$ in the resulting solution,respectively,are:
(Molar mass of $Ca(OH)_2$,$Na_2SO_4$ and $CaSO_4$ are $74$,$142$ and $136 \ g \ mol^{-1}$ respectively; $K_{sp}$ of $Ca(OH)_2$ is $5.5 \times 10^{-6}$)