Hydrogen gas reacts with oxygen gas to form water according to the equation
[tex] 2H_{2(g)} + O_{2(g)} --\ \textgreater \ 2 H_{2}O_{(l)}[/tex]
From the coefficients in the reaction equation, we can see that it takes two molecules of hydrogen to react with one molecule of oxygen. Since we begin with equal amounts of both gasses, we can conclude that hydrogen is the limiting reactant because we use it up first. Thus, we use hydrogen for our stoichiometry that follows.
[tex](6 molecules H_{2} ) ( \frac{2 molecules H_{2}O }{2 molecules H_{2} } ) = 6 molecules H_{2}O [/tex]
Thus, the answer is B, 6 water molecules are produced with hydrogen being the limiting reactant
