Question

B2H6 + 3O2 -> 2Hbo2 + 2H2O

What mass of water us produced if 1.38 moles of HBO2 are produced ?

How many moles of water are produced from 4.75 moles of oxygen?

How many moles of B2H6 are needed to react to produce 7.90 grams of water?

Answer 1

What mass of water us produced if 1.38 moles of HBO₂ are produced ?

n(H₂O) = n(HBO₂) = 1.38 mol

m(H₂O) = $1.38\;mol \times 18 \;g/mol = 24.84 \;g$

How many moles of water are produced from 4.75 moles of oxygen?

n(H₂O) $= \frac{2}{3}n(O_2) = \frac{2}{3} \times 4.75 = 3.16 \;mol$

How many moles of B₂H₆ are needed to react to produce 7.90 grams of water?

n(H₂O) =$\frac{7.90}{18.0} = 0.438 \;mol$

n(B₂H₆) $= \frac{1}{2}n(H_2O) = \frac{1}{2} \times 0.438 = 0.219 \;mol$