If $0.50 \ mol$ of $CaCl_2$ is mixed with $0.20 \ mol$ of $Na_3PO_4$,the maximum number of moles of $Ca_3(PO_4)_2$ which can be formed,is

$2 \ L$ of $0.2 \ M \ H_2SO_4$ is reacted with $2 \ L$ of $0.1 \ M \ NaOH$ solution. The molarity of the resulting product $Na_2SO_4$ in the solution is $X \ mM$. Find the value of $X$. (Nearest integer).

$1.0 \ g$ of $Mg$ is burnt with $0.28 \ g$ of $O_2$ in a closed vessel. Which reactant is left in excess and how much?

$A$ mixture containing $64.0 \ g$ of $H_2$ and $64.0 \ g$ of $O_2$ is reacted so that water is formed as follows:
$2H_2 + O_2 \rightarrow 2H_2O$
Which of the following statements is/are correct?

For the reaction,$2Fe(NO_3)_3 + 3Na_2CO_3 \to Fe_2(CO_3)_3 + 6NaNO_3$. Initially,if $2.5 \ mol$ of $Fe(NO_3)_3$ and $3.6 \ mol$ of $Na_2CO_3$ are taken. If $6.3 \ mol$ of $NaNO_3$ is obtained,then the $\%$ yield of the given reaction is:

$5 \, \text{moles}$ of $A$,$6 \, \text{moles}$ of $B$,and an excess amount of $C$ are mixed to produce a final product $D$,according to the reactions:
$A + 2B \to I$
$I + C \to B + D$
What is the maximum number of moles of $D$ that can be produced,assuming that the products formed can be reused in the reactions?