Question

non 7. You are holding four identical balloons each containing 10.0 g of a different gas. The balloon containing which gas is the largest balloon? (4 pts) A) H B) He C) Ne D) 02 E) All have the same volume. 8. How many liters of H2(g), measured at STP, are needed to combine exactly with 1.5L of nitrogen, also measured at STP, to form ammonia? (8 pts) 0. What yolume of carbon dioxide measured at STP will be formed by the reaction of 1.47 mol of oxygen with 0.900 mol of ethyl alcohol, CH,CH2OH? Hint this is a combustion reactions HO will also be produced (pts)

Answer 1

1.

At constant temperature and pressure

Volume $\propto$ Number of moles

mole = (mass/molar mass)

moles of H₂ = (10÷2) = 5

moles of He = ( 10÷4) = 2.5

moles of Ne = (10÷20) = 0.2

moles of O₂ = (10÷32) = 0.3125

So, Volume containing Hydrogen gas has the largest ballon.

2.

Balanced reaction is

N₂ + 3H₂ $\to$ 2NH₃

1 volume of Nitrogen reacts with 3 volume of Hydrogen.

so, at STP

with 1.5 L of Nitrogen reacts with 3×1.5 = 4.5 L of Hydrogen .

3.

CH₃CH₂OH + 3 O₂$\to$ 2CO₂ + 3 H₂O

1 mol Ethanol reacts with 3 mole oxygen to form 2 mole carbon dioxide.

Hence,

0.9 mol Ethanol reacts with 0.9×3 = 2.7 mol oxygen.

hence, oxygen is limiting reactant.

now mole ratio of oxygen and carbon dioxide

= 3:2

hence, moles of carbon dioxide can be formed

= $\frac{2}{3}$ × moles of oxygen

= $\frac{2}{3}$ × 1.47

= 0.98

now, volume of 1 mole carbon dioxide at STP = 22.4 L

hence, volume of carbon dioxide at STP = 22.4× 0.98 = 21.952 L.