Explanation:
<h2><em>Explain</em></h2><h2><em>Explainexplain</em></h2><h2><em>Explainexplainexplain</em></h2><h2><em>Explainexplainexplainexplain</em></h2><h2><em>Explainexplainexplainexplainexplain</em></h2>
1 Gallon = 3.7854118 Liters
Answer: The missing coefficient is 2.
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

As in the products, there are 2 atoms of sodium, thus there will be 2 atoms of of sodium in the reactant as well. This will balance the number of hydrogen and oxygen atoms as well.
Thus the missing coefficient is 2.
Answer:
4 moles
Explanation:
=
= 2 (moles)
CH4 + 2O2 → CO2 + 2H2O
1 : 2 : 1 : 2
2 (moles)
⇒
= 2 × 2 ÷ 1 = 4 (moles)
Volume of H2 produced = 57.6576 L
<h3>Further explanation</h3>
Given
23.17 g Be
Required
Volume of H2
Solution
Reaction
Be(s)+H2O(g)→BeO(s)+H2(g)
mol Be :
= 23.17 g : 9 g/mol
= 2.574
From the equation, mol H2 : mol Be = 1 : 1, so mol H2 = 2.574
Volume H2(assumed at STP, 1 mol=22.4 L) :
= 2.574 x 22.4 L
= 57.6576 L