The amount of $BaSO_4$ formed upon mixing $100 \ mL$ of $20.8 \%$ $BaCl_2$ solution with $50 \ mL$ of $9.8 \%$ $H_2SO_4$ solution will be ............. $g$
( $Ba = 137, Cl = 35.5, S = 32, H = 1$ and $O = 16$ )

If $0.5 \ mol$ of $BaCl_2$ is mixed with $0.1 \ mol$ of $Na_3PO_4$,what is the maximum number of moles of $Ba_3(PO_4)_2$ formed?

The mass of water produced when $4 \ g$ of hydrogen reacts with $4 \ g$ of oxygen is .......... $g$.

What is a limiting reagent?

How many moles of $P_4$ can be produced by reaction of $0.10 \ mol$ $Ca_5(PO_4)_3F$,$0.36 \ mol$ $SiO_2$,and $0.90 \ mol$ $C$ according to the following reaction?
$4Ca_5(PO_4)_3F + 18SiO_2 + 30C \to 3P_4 + 2CaF_2 + 18CaSiO_3 + 30CO$

$2 SO_{2(g)} + O_{2(g)} \rightarrow 2 SO_{3(g)}$
The above reaction is carried out in a vessel starting with partial pressures $P_{SO_{2}} = 250 \ mbar$,$P_{O_{2}} = 750 \ mbar$,and $P_{SO_{3}} = 0 \ mbar$. When the reaction is complete,the total pressure in the reaction vessel is $..... \ mbar$. (Round off to the nearest integer).